CXC MATH 2026 PAPER 2 MAY 12

追加: 2026-05-13

[00:00:00]All right. So given f= 3x + 1 / 2. Determine the values of g 0 + g5. So all we need to do is just substitute the value of ng for both of them. So do g 0 first.

[00:00:23]So 3 * 0 + 1 / 2, which is 0 + 1.

[00:00:30]So the first one works out to a half.

[00:00:33]And then for G5, it's 3 * 5 + 1 / 2 3 15 + 1.

[00:00:44]So it's 16 / 2, which is 8.

[00:00:48]And of course, it's the sum.

[00:00:51]So we add both of these 8 + a half which equal 8 and a half that will give us our full marks.

[00:01:05]We use a factor, right? All right. This one says FG. So the rule says we write back G first.

[00:01:14]So G is 3x. I'm going to just over here.

[00:01:18]G says 3x + 1 / 2. So write back all g.

[00:01:27]Put that in bracket. Why we do that?

[00:01:30]This is our x in f.

[00:01:33]So this going become x and of course we have four. This is x - 7. Consider this as all over one. All over two rather. So 4 * 3 12 4 1's 4 4 - 7 and of course 12 x - 3 / 2. Now we're not finished because they ask us for fg 5. So now we're going to substitute 5 in the equation.

[00:02:15]So anywhere we see x, we're going to put five.

[00:02:21]So that's 12 * 5, which is 60 - 3.

[00:02:31]So this is 57 over 2.

[00:02:40]I literally said that you know at the start of the class I said we do the first two but we didn't do fg we didn't do the inverse yeah I did say it see >> okay sir >> so do the inverse now on one I did say it man probably I didn't hear so guys inverse f But as I also said that our speed have to be a little bit cuz I want to go through as much as possible. So your speed have to be a little bit faster than usual.

[00:03:17]All right. So the answer for the inverse of f. Now f is fx = 4x - 7. All right. How do we find inverse? We just do the opposite of whatever is happening when it come to functions. Right? So therefore y= 4x - 7. We interchange x y and y x. So you have x = 4 y - 7. And then now at this point you just solve for y. So you make y the subject of the formula. So I get rid of the - 4 * y. Now the opposite of - anything I do to one side I do to the next side.

[00:04:02]And then of course we divide by four cuz that's the opposite of multiplication.

[00:04:07]So this is the inverse of f. Now they ask us to put one now. So anywhere x is we put one.

[00:04:15]So be 1 + 7 / 4 which is 8 / 2 8 which is equal to two.

[00:04:26]So that will be our answer.

[00:04:38]Yeah. Two. Remember when you find the inverse of f, you're going to basically plug in one. Anywhere x is, you substitute one and then 1 + 7 is 8ide by 4.

[00:05:10]I didn't finish right almost. Mhm.

[00:05:33]finish.

[00:05:35]>> All right, I'm recording here.

[00:05:44]Try that one, guys.

[00:05:48]All right. So we have points P61 and Q2 27.

[00:05:57]These are the end points of a line segment. PQ PQ determine the gradient.

[00:06:01]Now the gradient is basically the slope.

[00:06:04]So it's Y2 - Y1 / X2 - X1.

[00:06:11]So we can yeah we can just label them.

[00:06:15]This a x1 y1 this x2 y2 and it doesn't matter which one you label as long as you have x1 and y1 together. All right. So y2 would have been 7. So 7us now this is -1. So it's going to put another -1 and then of course 2 - 6.

[00:06:45]So this becomes a plus. So it's 8 over 2 - 6 would give us -4. So the gradient is -2 and you would have gotten two marks for that.

[00:06:58]So it's basically the slope of the line.

[00:07:05]>> Please don't move it >> sir. So when >> sir >> Mhm.

[00:07:13]>> when you have two minus your plus >> definitely when they together.

[00:07:21]>> Okay. coming up.

[00:07:34]>> Oh, come >> on. Too fast. Just give me one more second back on it again, please.

[00:07:52]>> All right, no problem, man.

[00:07:55]So, this are the formula, right? I know some people like formula. I don't think this is on the formula sheet. I think we have to know this one out of our head.

[00:08:04]So, just remember y up the top, right?

[00:08:06]All right. So, it's y2us y1. Now, the value, you can name any one of them. We could name this x1 y1, but as long as they are together, the x1 and the y1 and the x1 the y2. All right? So, it's y2 - y1. So, it's seven because you have a -1 here. So, youus -1 because a minus is a part of the formula. And then you have x2 which is 2 - 6 because this is pos 6. We don't have anything else. Now this becomes a plus.

[00:08:44]So it's 7 + 1 / 2 - 6 will give us -4.

[00:08:50]So it's 8 over -4 which is -2.

[00:08:57]That will give you the gradient.

[00:08:59]>> Thank you sir.

[00:09:00]>> Yeah man. No problem.

[00:09:13]Just remember guys, it's it's y2us y1 not the other way around.

[00:09:20]So the y must up the top. All right. So it asks now for the coordinate of the midpoint. So you're finding the midpoint.

[00:09:29]You need the information of the point here.

[00:09:35]So find the midpoint.

[00:09:38]All right. So to find the midpoint, this is the formula. Again guys, this is not on it. We did this. Let me tell you when we did a topic here for October. Anybody can confirm.

[00:09:55]Think about October.

[00:09:58]So it's x1 + x2 and y1 and you divide by two. So it's half. It's really a coordinate you're finding. So you have x y x y. So you add the x terms. So it would have been 2 + 6. Put your comma a coordinate finding. Then you have -1 + 7ide by two.

[00:10:29]So this will give you 8 / 2 and this will give you pos6 / 2. So it becomes 43.

[00:10:42]So that's the midpoint or the coordinate of the midpoint. And what this does it basically cut the graph in two.

[00:10:51]So if if if the graph stay like this that means from here to here would have be the same length as from here to here for example.

[00:11:03]So that's the coordinate of the midpoint. So this point here would have been the 43. So just in case they give you a graph or they ask you literally could use a ruler. I remember I was in a class and a guy did that and he said, "Sir, you know, say I literally just measure it."

[00:11:24]So, hold on. I think this person is supposed to be on All right. So it says the equation of the perpendicular bis sector. So we basically need the coordinate which was what? 43 of the midpoint. So we're going to need that.

[00:12:40]So 43 and of course was it 34 or 43?

[00:12:49]Oh see 43 and this is how CC set it up sometimes. All right they're going to put it in order. So you use already we're going to use again. All right. We also need the gradient this. Hey, this work more than two marks, you know, but I think because we already did that part up there. So, so yeah, the expected just kind of All right.

[00:13:16]So, one thing guys, we we need we take the negative reciprocal of this. So, as it stand the gradient is -2 over 1. So, the negative reciprocal would be positive a half. All right.

[00:13:33]positive.

[00:13:35]All right. And then you use this formula which is y - y1 = x - x1.

[00:13:44]And we're going to use the points now to substitute in these values.

[00:13:50]So y 3. So we're going to say y - 3 = the gradient which is a half x and of course four.

[00:14:02]And then you can take it from there.

[00:14:03]Half times that would be half x. Half * this would be minus 2. Just in case somebody wondering, this is the same as this, right?

[00:14:17]So we have minus three here. So we add three to both sides.

[00:14:26]Say half x. Now this work out to positive one instead of five it should have been one. Good job.

[00:14:41]So use the midpoint and also the gradient and that is why they kind of do it. So you do both of them.

[00:14:50]All right. So they say take the coordinate of E. So you just find E which is this point here.

[00:14:57]Right? And of course they're going up by one. So this would have been 4 1 2. So 42.

[00:15:06]So that's the coordinate of E.

[00:15:09]And it said describe fully the transformation D E F2 this one. So you can just take the point 42 right which was what? E.

[00:15:27]and that becomes -24.

[00:15:32]So it's a anticlockwise of 90°.

[00:15:40]So they're going anticlockwise going to the opposite direction and is 90°.

[00:15:55]Let's move on to the next one. Guys, if you can't write fast enough and you don't want to watch back the video, you can screenshot it. All right.

[00:16:09]>> You can just imagine like your phone, you know, guys. They literally have a phone up pictures and something you must know a rotation of 90° and >> sir >> um for the coordinates right the four two >> all right >> I understand how you get the four right cuz it's right here on the line >> but the two what you're writing couldn't you just use where d is come out to the Y line by Yaxis.

[00:16:46]>> But that's what we did.

[00:16:48]>> It's intersection of both of them. Yeah.

[00:16:51]>> Okay. Okay.

[00:16:52]>> Mhm.

[00:16:54]>> All right.

[00:16:56]So, screenshot if you're having a little problem. Oh, see done. Sorry.

[00:17:01]Need to go paper them first. It say on the grid above draw the triangle D E F the reflection. I'm going to just do that guys because for us to draw that but I want you guys to tell me where it would be. Where would be the reflection?

[00:17:17]I >> think somebody was asking me where >> the y ais >> it say in the x-axis. So put it y ais x ais. So um which one they ask for? D prime. All right. So and they want it for this D E F right. So they want this one.

[00:17:40]They want a reflection for this one.

[00:17:45]>> Yeah. So it be over here. So if if this is the x-axis >> and to reflect it, you just put each one of them the same distance. So this would have be >> this would have be one. You move one.

[00:18:01]And then you have one, two, three, four.

[00:18:04]When I was teaching this to grade four, we did we didn't put no card. We just count and then you know one two three four. So you count four down. One 2 3 4.

[00:18:20]They like to give you these little things, you know. So you have to reflection. It look just like think of yourself looking in a mirror. You're not see your head back. You see your nose like your nose. The closer you go, it seems like your nose touch your nose.

[00:18:37]>> It's the same thing. All right.

[00:18:41]Absolutely love to give this on the table. For those who were attending the nightly marathon, you should be able to just run through this cuz we have done so many of these. These are very popular with sexy.

[00:18:54]All right. So, have fun with these. I'm going to give you a little bit more time because I think this one require some more work. Let me look on it.

[00:19:05]All right. So it says a sequence of figures is made up of units squares with unit size. First three figures in the figure and we just figure one right just one little box and then we can kind of pick up the pattern what's happening.

[00:19:21]What I observe I just put this as one and then you have one two one two one two. Put this as one.

[00:19:31]two. So this was the original for figure two. And you can see they just add one box each way.

[00:19:41]So that means for the figure four, you're just going to have one box added to each one of them. So this is four.

[00:19:50]This is four.

[00:19:53]No, this was supposed to be three.

[00:19:56]Then four.

[00:20:00]Then four and that will be figure four.

[00:20:04]Dry it from scratch. But yeah, you just add one and you get two marks for that.

[00:20:10]All right. This have a particular way that you can do it. First you have to observe, right?

[00:20:15]>> Sorry, I can't go back up please. See that >> I just added to this something that already exist. But if I was to draw it, it would have be something like this.

[00:20:30]Four.

[00:20:34]One, two, three, four.

[00:20:39]Two, three.

[00:20:41]It's based on the pattern that they had, right?

[00:20:47]You just observe and see what from figure one to figure two to figure three to figure four and so on.

[00:20:55]>> So why you write one twice? H >> why you write one twice?

[00:21:02]>> That was an error.

[00:21:06]>> Yeah.

[00:21:11]So sorry about that. All right. So that's it.

[00:21:16]>> So sir sir, >> basically you're going up four every time. So you put four more on it. No one put on it continually one you put on you know on on either side but three exists already >> on each side >> four on each side just one oh you mean unless you're saying there should if it's figure four that mean four should be on that >> yes yes yes Yeah, but you say going up by four. So it's going up. Yeah.

[00:21:59]>> So if it was figure five, it would have be five, five, five, five. And the one in the middle.

[00:22:04]>> Mhm.

[00:22:06]>> Yeah. So you just have to look at the pattern whichever they give you. It's just observation really.

[00:22:13]All right. For this one now guys, you can literally think about it in this sense. So figure one is have one which was that what they gave us and then the perimeter would have been four for this two five for this you can just kind of figure this out by looking at the >> excuse me sir >> yeah man go ahead >> for the perimeter I figure each one going down say we add eight >> yeah so you guys look at it a lot of people look at it that So if you and if you look on it that way they have to list out from one to 30 to get 30. So I show you easier man. All right. So you have the difference here would have been what? Four, right? The difference here is four as well.

[00:23:05]>> So we can just use that and say probably they multiply four times a number call it n. All right. And then whether they add to a number I'm just using this you know and it equal to one.

[00:23:24]So if we say x is 1, n is one. So we can say 4 * 1 plus a number and it give you one. So basically we can see that they subtract three.

[00:23:39]Right? So that's the pattern.

[00:23:42]We prove it's a type pattern. So we have four for figure two. 4 * 2 - 3. 4 2 is 8 - 3. You see it give you the five. Let's look at this one now. 4 * 3 - 3. 4 3 is 12 - 3 9. You see I I know CXC give you this last but I when I when I'm doing it I try to figure it out first. So it's 4 n - 3 for every one of them that is in this this 4 n minus 3 will give you the figure. All right, for this one now the difference of eight just like what someone was saying a plus 8 + 8 but look that mean actually times by eight you know so we can use the first one to figure it out we have 8 n plus a number and it give you four.

[00:24:43]So if 8 and a one right which is figure 1 8 * 1 + x so 8 1 are eight so we can see that they subtract four in order to get it. So this one would have been 8 n - 4 and we could try it for the next one. 8 * 2 that's 16 - 4 give you the 12. You see? All right.

[00:25:12]Look here now. 8 * 3 - 4. 83 is 24 - 4.

[00:25:18]You see, you get the 20. So for this one, we're going to use 4 n - 3. So 4 4 16 - 3 11 4 16 - 3 11. And then this one now 8 n >> 13 sir >> 13 from 6.

[00:25:44]>> So 82.

[00:25:47]>> Yeah man. It's okay.

[00:25:52]>> So this one now they're very smart. You know they always going to give you this and say yo figure that one here. But because we know the formula already then all we have to do just say just literally put it in this right equate it. So it'll be 4 n - 3 give you 45 cuz that's how we get the 45 in the first place. So if we figure out this we can figure out this.

[00:26:19]All right. So this minus three. So we add three to both sides becomes 48 and then we divide by four.

[00:26:30]So this will be figure 12 based on that.

[00:26:34]Agree?

[00:26:35]>> Yeah. Yes.

[00:26:35]>> And then and then 8 * 12 - 4 8 nus 4 for this one. So it be >> 12.

[00:26:47]>> Yeah. 96. So 96US 4 which is 92 >> just once you find once you know this you can't find anything else um 30 4 * 30 120 - 3 that 127 8 * 30 240 240 - 4 about 236 and that's it.

[00:27:18]We don't want to lose 10 marks here guys because usually >> go ahead sir.

[00:27:25]>> No man usually they bring this and it worth 10 or eight marks. So you know sometimes it's more challenging but most times it's something like this.

[00:27:36]Sometimes they give you a figure but you know once you figure out the table you can see that they multiply.

[00:27:43]Guys you can't figure this out. Nobody never teach me sit and see.

[00:27:49]>> All right, sir. The formula part, right?

[00:27:53]How you find the 4 n minus three? I did it a different way.

[00:27:58]>> I just take take away the one from five, leave four. So I put on the four and I put the n.

[00:28:05]And then I said, what >> can I add or subtract to four?

[00:28:13]You get back the six.

[00:28:15]>> Yeah. Six. Oh >> yeah.

[00:28:20]>> And it is three.

[00:28:22]>> Yeah. Literally >> for the >> for the eight now minus the four from the 12 I get 8 n. And then I said what can I add to that to get back four is minus four.

[00:28:39]>> Yeah. So guys, you see it because you see you have to go add it 30 times.

[00:28:52]Add that all of that. So you don't want that because 125. You're going to do that. That's going to take up all of the exam time.

[00:29:02]So once you figure out the pattern and the formula, then you can use it.

[00:29:08]Yeah, man. Go ahead.

[00:29:14]All right.

[00:29:16]So that I give it 10. Nice. 10.

[00:29:23]All right. This one. Now the table shows a pair shows pairs of values X and Y where Y is inversely proportional to X.

[00:29:33]So you have the direct proportional and you have the inverse proportional. This one is the inverse.

[00:29:40]Express Y in terms of X as X and a constant K. So that's the first part.

[00:29:47]And then they say calculate the value of the constant K. Once you find K, you can find any number.

[00:29:57]All right. So based on the table, it says express Y in terms of X and a constant K. So it should have been y = k /x. You have to know the inverse versus direct.

[00:30:13]All right. So that will give you the one mark. And now they say calculate the value of the constant k. So what I usually say to students, you're going to use the ones that well you can either use this or this. You have both of them and you can substitute the value. So we know x be and y be two. So we just put it for here. So once you know the formula work for you we don't know what k is search for. So since y is going to be two we don't know what k is but we know that that is three and then we basically solve for k. So this will divide your times by 3. So K is = 2 * 3. So K= six.

[00:31:08]Once you get K, you're good to go.

[00:31:13]Can find any one of them. So find a say K.

[00:31:22]So we know Y = K / X. But we know say in this case we're searching for X. So we know what Y is. Y is 1.2.

[00:31:36]So it's 1.2 = 6 over X.

[00:31:44]So K 6 we don't know X. Yeah. So that be X * 1.2. So 1.2 2 x = 6 and then we divide by 1.2 so x = 5.

[00:32:08]So let's figure out b now using the using this right. So we know say y = k / x y we don't know what y is in this case.

[00:32:28]So y b we know say this a six which is k and x be 20.

[00:32:42]>> Yeah.

[00:32:44]So you just reduce it to 3 0.3. So >> yeah, since they gave it as a decimal.

[00:32:59]So what happened? You can see that that would be the same 10 is the same as 0.3 as it part. So once you know you should know the direct one which is what y = kx versus this one.

[00:33:34]I had to I had to dig up this one guys.

[00:33:36]says I write x² - 6 x + 8 in the form a bracket x + a 2 + k where a h and k are constants that probably were three marks let me say how many or two three yeah man say this take a bit all right so we're going to write x² - 6 x + 8 in the form a x + 8 + 8 where all of these are concerned right so the first want to do let me just rewrite it first so the first bracket x term now once you see this you know make it feel comfort right so you have 1 - x² All right. So the next thing you want to do, you want to find the half of the x term and square it. So it'll be 6 x half of this will be three, right?

[00:34:49]And then square it. So it will be -3 * -3 which is 9. So we add in a positive 9.

[00:34:59]But whatever we add in we have to take out to balance the equation. So because we add 9 here we have to subtract 9 there.

[00:35:11]So it will be x² - 6 x + 9 a take 9 that's -1 and then all we have to do oh lord all we have to do is just factoriize this right and it would have been x - 3^ 2 - 1 and of course a one can factoriize it the long way Okay, two numbers when you multiply them they give you positive 9 and when you add them you give you three set of x - 3 x - 3x you really care if you do this though so x prime that leave x - 3 x into that leave - 3 so that be x - 3 and x - 3 which give you this. So this is how we get the x - 3 which is this. But remember any number you square that's that is it. So we squared -3 to get that body f you guys not see my screen.

[00:36:36]>> I'm seeing it.

[00:36:38]>> I'm just seeing your picture.

[00:36:40]I'm sorry.

[00:36:43]>> Rejoin.

[00:36:50]>> Yeah.

[00:36:52]>> Yeah. Quickly. So you can see.

[00:36:55]>> All right. So they want us to find H K L. Remember it's the one in the middle.

[00:37:01]That's the angle, right?

[00:37:04]So, H K L would be this angle right here. Guys, if we kind of figure them line here, right? And this line here and this line here, then you can see that it's angling the same segment, right? This is 20°.

[00:37:29]line to kind of try confusing.

[00:37:36]So it's angling the same segment or equal.

[00:37:50]All right. So they wanted to find J.

[00:37:51]Okay. No J. Okay. Well, let me just write it up here. So J. Okay.

[00:37:59]that there.

[00:38:02]Okay. J. So J.

[00:38:22]All right, guys. Want to focus on this triangle here. I'm going to put it in a different color.

[00:38:29]The thing with circle have to kind of just see what's happening.

[00:38:34]You know, you can't get it from down here.

[00:38:41]This is triangle, right? Oh, I know that. Hold on. Which part the center again?

[00:38:57]There's no sir.

[00:39:00]>> Oh yeah yeah yeah yeah.

[00:39:02]So basically one of this you know one.

[00:39:11]Yeah. So this one 50 right. So we can this is a radi. This is a radi that mean it's an isosles. So this is also 50.

[00:39:22]So it be 180us 50 if Ios both angles are 50 wus 100 so that's 80° so Okay. Okay. That'll be 80.

[00:39:59]I think it's a little bit more easier.

[00:40:01]No.

[00:40:04]Oh, again this.

[00:40:08]Oh, yeah. Yeah. Yeah. Vector.

[00:40:12]Let's up, guys. Write the column vector in the form XY and they ask for OP and the vector QR and that will give three marks and see the big deal with this Y one and two one and three one. I don't see it.

[00:40:46]It's literally the same thing, guys. You have to look carefully, right?

[00:40:52]You see where Q is is not O. You know, O is right here.

[00:41:00]So, we want the vector O P from O to P.

[00:41:03]So, this is the vector that we're looking for.

[00:41:10]And we can just count start at O 1 2 3 4 units and you go down one. So OP of 41.

[00:41:26]I think somebody said this wrong, you know. Sorry.

[00:41:32]Thought it was QP. All right. Sorry, my bad. Um, so they want QR now from Q to R. And guys, you don't need no fancy thing with vectors. You can look at the vector itself from Q to R, right? Start here.

[00:41:49]I'm going to go there. So 1 2 3 and then 1 2 3 4 5 up. So that's 35.

[00:42:05]Argument.

[00:42:07]So that's 35.

[00:42:11]Yeah, I was supposed to do this at >> fine, man.

[00:42:20]>> Nothing so good, man.

[00:42:27]>> Scroll down.

[00:42:29]>> Small it up. That's the entire thing together.

[00:42:33]>> Scroll down. Scroll down. So, we see half of it.

[00:42:39]Yeah.

[00:42:39]>> All right. So Q Right.

[00:42:43]You about three. One, two, three.

[00:42:49]>> R.

[00:42:50]>> One. Yeah. One, two, three. One, two, three, four, five.

[00:42:59]So why get seven?

[00:43:02]>> Well, probably need glasses.

[00:43:06]because it remember start >> Yeah. But I'm saying if you're going to look at it seven looks >> not coming from here in terms of QR.

[00:43:34]>> Okay. Is that all right?

[00:43:46]>> Yeah. Yeah.

[00:43:48]>> Yeah. You can just minus the two from the seven, you get the five >> and the three zero from the three and you get three fives.

[00:43:58]>> Mhm.

[00:44:00]Mhm.

[00:44:03]>> All right.

[00:44:06]Further. As I said, this are the easier part of the lesson cuz I figured start off with a border first. So, this is how number one usually look. So, have fun with that.

[00:44:25]This one hear the recording, man.

[00:44:35]Oh, that messed up my laptop a lot. All right. So, we have 5 and 12 / 3 and 2/3 plus 1 and 4. Give your answer as a fraction in its lowest term.

[00:44:47]Let me use block.

[00:44:50]So you have to do the division first, right? I'll do it the front. But yeah, make sure guys you don't get mixed up with it. Division before addition, subtraction. Remember multiplication and the bracket and the all of those rules for order of operation. So 5 10 + 1 11 / 2ided by 3 is 9 + 2 11 / 3. Let's put the plus 5 9 right now just carry down. So the rule say keep change flip.

[00:45:32]So 11 we cancel 11 right. So this work out to 3 / 2 + 9 over 5. Find your LCM.

[00:45:40]Once you're adding and subtracting find your LCM which should have been 10. 2 into 10 goes five times.

[00:45:48]3 5 15 and then 5 into 10 goes 2 * 9 2 is 18.

[00:45:59]So 1 2 20. So that's 33 / 10 or 3 which is 30 and 3.

[00:46:11]This cannot be broken down any further.

[00:46:13]You go too fast.

[00:46:16]Oh, where this part?

[00:46:23]Run it back.

[00:46:25]Sir, I don't get Oh, you get the 18 >> 18. Oh, 5 into 10 2 * 9 2.

[00:46:37]Yeah. So, it's 11 / two, right? You change division to multiplication and then reciprocate. So we use 11 cancel 11. So you see over two. So 11 cancel itself cuz it goes one time. That left us with 3 / 2 and then we just add 9 over 5.

[00:47:00]LCM is 10. Right? So 2 into 10 5 * 3 5 and then 5 into 10 2 9 2 18. And from here we just add. So that's 33 and a half hours. But yeah.

[00:47:33]All right. For the next one. Now just draw one calculator.

[00:47:40]165 * 0.38.

[00:47:43]Guys, you can just put this in your calculator, right? So, we know supposed to square this first 0.38 time 0.14.

[00:48:05]So 0 1 4 then just put in your calculator times 1.65 165 * 165 23.8 8 exact value.

[00:48:27]So it's 23.

[00:48:30]I think somebody roll it up guys. Why you say exact?

[00:48:35]>> Yes. Somebody up to 24. Please not do that guys. This is the exact value.

[00:48:42]Never say to one decimal, two decimal or nearest whole number. I just realize it's the exact value they want. So give them this please.

[00:49:02]>> Yeah. All right, guys. But guess one more time.

[00:49:10]Write your answer. It's too Oh, man. Hold on. Hold on. Let me see.

[00:49:22]This is a Yeah. So, um the right to hold on.

[00:49:30]Um what number again? 23.86.

[00:49:34]>> 23.826.

[00:49:37]>> Yeah. Yeah. Number 23.826.

[00:49:42]So don't want to do two decimal place, three significant figure and some other things. So shop that fast guys and to the nearest whole number.

[00:49:52]>> Nearest whole number.

[00:49:53]>> Yeah. Yeah.

[00:49:56]All right. So two decimal places mean two number must come after the decimal point. So we have the decimal point here. So these are the first two numbers has come after it. But we have to check on this one. If this is 5 6 7 8 9. Yeah, round up. So you round up. We're going to add one to the two to make three. So 23.83.

[00:50:23]Three significant figure mean important.

[00:50:26]Right. So the first three figures 1 2 3 you check that one year. Since a two we just drop it off. So it's 23.8.

[00:50:35]And to the nearest whole number this is.8. 8. So we round up. So we add one to this to give us 24. Nice three marks there. No one should get that incorrect. It's coming.

[00:50:52]>> Question sir, if I had the two is still correct, right?

[00:50:56]>> Yeah, man. 24. Back up, sir, please.

[00:51:00]>> Okay, I saw what you did.

[00:51:03]It's fine.

[00:51:05]Still 24.

[00:51:15]Sir, how you said they got the three significant figures again?

[00:51:19]>> All right. So, it's it's important, right? Three important figures. In this case, we have 23.8.

[00:51:27]So, you check the two. Since the two is less than five, we round down. So, it's 23.8.

[00:51:37]Okay, thank you.

[00:51:39]>> Yeah, before you go, you can drop to simple interest, please. Refresh as a refresher.

[00:51:50]>> Well, not me have that because we already gone through that in the regular one. So, I didn't add it. I don't think none of those is is there.

[00:52:01]>> All right.

[00:52:03]>> Yeah. But um if you could have find the previous I think you guys would have done simple interest and compound I think so that's why never put them look for the ones we never do much of so you know so everybody can't be ready.

[00:52:31]All right. So it says what given that a series b is equal to a + 4 b square root of course where the positive root is taken determine the value of one asteric 2. So we know that the first one is a and the second one is b. So therefore a = 1 and b = 4. So it's 1 + 4 * 2 which is 4 2 8 square root of 9 which is equal to three. So that will give you nice two marks. All right.

[00:53:18]State whether the operation denoted by star is commutative. So if you commitative it means that if you turn it around both of them should give you the value.

[00:53:30]So this time make a = 2 and b = 1.

[00:53:34]That's what they mean you know. All right. So first one be 2 + 4 * 1 4 6. You're supposed to get back the tree.

[00:53:53]We didn't get back she so it's not we justify all right solve the inequality one minute please >> before >> sir you're you supposed to have >> you >> what did you do You add the four to the two. Is it >> 4 * 2? 4 * 2 >> + 1 is nine.

[00:54:33]>> Mhm.

[00:54:35]>> And then the square root of 9.

[00:54:38]>> Yeah. Which is three.

[00:54:42]>> No man, the last one I'm talking you have the square root of six, which is three.

[00:54:49]But if it's equal to three, the top one was also equal to three.

[00:54:53]>> No, this is not three. Remember 2.3 or something?

[00:55:02]>> Okay.

[00:55:04]>> This one legit. This one three. They don't equal. They don't equal.

[00:55:10]Sir, >> I used to make um an adjustment to B= 2 instead of 4.

[00:55:21]>> Four.

[00:55:23]>> Yes. The value of 1 * a = 1 = 2. But you have = 4.

[00:55:32]>> No man. Be a one. See here.

[00:55:36]>> No, not not that one. The one before >> this.

[00:55:39]>> No. up top >> top. She talking number one.

[00:55:43]>> Yeah.

[00:55:44]>> Okay. Okay.

[00:55:46]Mhm.

[00:55:48]As if the four really come from the B 4B.

[00:55:54]Yeah.

[00:56:00]But everybody get the idea. Um we just turn it around to see because Yeah.

[00:56:06]And if it come together, we know it it's not supposed to get back the same of the both.

[00:56:16]And we didn't solve the inequality 3 - 2x greater than 5 and represent the answer on the number line show. So that's three marks.

[00:56:36]Just do your best, guys. That's all anybody can ask for. Your best. Your best. Your best. That's it. All right.

[00:56:43]So, it says solve the inequality.

[00:56:46]3 - 2x.

[00:56:49]Guys, remember, you know, don't put equal sign in there. All right? Don't put equal sign. Use the sign that they give you.

[00:57:00]All right? So this is a - 3 positive 3 rather. So you go - 3.

[00:57:08]So you're going to get - 2x greater than 5 - 3 2. This is where the tricks come in. Now you see when you dividing by have to change the sign.

[00:57:23]So this2 no confusing. Hold on guys.

[00:57:31]So this is what we have, right? And we're going to divide by minus2. So you divide both sides by minus2.

[00:57:39]So this means you turn around the sign and of course that's -1. So there we all find one. Notice there's no line underneath it. If a line underneath it, you block it out. If not it remain a open circle like that and of course the values less than negative one will be all of these values going this direction.

[00:58:12]All right so guys I end there for today tonight hope you guys get some rest um yeah you know it's important for rest before the the day. So, all the best everyone.

[00:58:28]>> Sir, >> are we going to be having um pass papers tomorrow?

[00:58:40]>> Pass papers? You mean multiple?

[00:58:43]>> M. Yes, >> of course. Why would I stop one exam? A lot of people make it look like multiple choice is not a part of the exam. It's really one exam. So you want to score as much as you can. So yeah, two question two questions sir. So when you start doing the multiple choice, you're just going to work through multiple choice pass papers.

[00:59:12]>> Definitely. Yeah.

[00:59:13]>> All right. Good. And the next day is it true that we can't water in the exam tomorrow >> my son my son school you cannot car water >> but >> and I heard somebody else say that >> I think it's probably true you know because at my school they normally provide water in a big igloo so I think it could be true you know >> sir they say that we can take water but we cannot let it catch the paper So maybe that's the reason why they cut out the water from going in because not everybody can control the water that they taking in.

[00:59:51]>> So the kids can't control.

[00:59:53]>> I'm not sure because when I did exam they said no water and we adults they say that we have to put it like if we won't wet the paper then that's fine.

[01:00:04]>> Okay.

[01:00:04]>> But it can't be on the decks that you're working on. So put it on the ground.

[01:00:16]>> Yeah, that's what I'm saying. Yeah. So focus probably drink the water before you do the exam.

[01:00:23]>> Carry my vitamin water to be cold.

[01:00:40]>> Two people carry one.

[01:00:44]>> Yeah.

[01:00:46]Yeah.

[01:00:47]>> Yeah. So do it for real >> because once you look on the paper, they not going to give you a chance to go to the bathroom by yourself.

[01:00:54]>> Yeah.

[01:00:56]>> Okay.

[01:00:58]>> First do it. So they have strict something in place.

[01:01:04]>> Um sir for the for the math um what do we need? We need can we use pencil?

[01:01:10]>> Only to draw diagram you have to use pen.

[01:01:13]M >> if you use pencil guys at your own risk >> and then you cannot use paper liquid.

[01:01:23]>> Yeah, >> you have to put the geometry set and that's alone. Remember >> I heard that you have to bring it into a a clear plastic bag.

[01:01:39]>> Yeah.

[01:01:40]>> So that they can see through it.

[01:01:42]>> Yeah. You can't carry a black bag and a granny thing. You understand?

[01:01:46]>> Paper in the calculator. You can't carry the paper in the driver said you cannot carry it.

[01:01:52]>> No. And and you also have to bring your ID with you. So make sure you have your ID with >> Yeah. Like your passport or whatever, >> right? And also your time table. So don't forget those.

[01:02:07]>> Yes. Don't forget the time table.

[01:02:10]>> Yeah. Put them together from tonight, guys.

[01:02:15]>> And don't wear any spaghetti strap or any ripped jeans >> and no flipflop.

[01:02:24]>> Yes, sir.

[01:02:24]>> No, sir.

[01:02:27]>> When I did when I did English, um Yeah.

[01:02:32]>> Okay. Fire was known.