May 2014 Mathematics HL Paper 1 TZ2

[Dotty]

Hey guys how did you find the maths Hl paper 1? It was more difficult than I expected! I didn't know what was about the last question, the one about the arctanx etc.

[Negotiation]

The paper seemed longer than I expected, but maybe that was just because of the pressure. Anyway, it worked out quite nicely in terms of time.

I managed to complete all the questions, though probably not with perfect accuracy, but I actually thought the questions were harder than I expected.

What did you guys think?

[XeoKnight]

I found it really easy but there were SO MANY QUESTIONS, so much to do! I knew how to do all of them but couldn't finish them on time, like for example a three mark q where you had to find a polynomial of 3 degree over (x^2+1)^3 took me ages to simplify, maybe cuz I'm just slow. TZ 2 here btw.

Oh yeah, I didn't really get the arctan one, I guessed sorta lol.

Edited May 14, 2014 by XeoKnight

[Negotiation]

Oh, I remember a question.

It had a drawn graph and asked to find stationary points and points of inflexion.

For the stationary points I believe I got x=1±root(2). This didn't correspond with the graph, which seemed to indicate something more like -1±root(2). So I went over the question for a few minutes trying to figure out where I went wrong.

Well, after the exam I graphed the equation, which I believe to have been (x-1)/(x^2+1)

Turns out x=1±root(2) was correct, it was just a different graph that was graphed. I believe it was (x+1)/(x^2+1).

I may be wrong and have read the equation incorrectly, but if this is intentional to mislead students from reading off the graph then that's... bad.

[Ckathy]

It's not difficult, actually I was supprised that it was much easier than the mock exam that given by my online math course. I was a little bit worried in the beginning because there were so many questions! But later I realized that I had enough time and I answered all the question. But unfortunately I didn't figure out one part of the last question which I think it was talking about"show f(x)=pi/2 when x>0"...I didn't get the language at all.

[XeoKnight]

Speaking of math, did any of you have to wait extra time as well? Apparently we got the wrong formula booklets so we had to wait an extra 30 minutes before the exam started so that they could print the right ones Our ib coordinator said everyone else had the same thing happen to them as well lol

[RG_2995]

I found P1 to be hard as in the questions were fine but I still couldn't do them and thanx to the time constraint couldn't finish the paper also!! I am really scared because there are a lot of blanks on the paper and wtv I did its not all correct.

So I am hoping for the gradr boundaries to be low but I guess that might not happen since everyone did well.

[tiffany_wu888]

whaaatt
my whole class thought it was overall harder than all of the past papers!
LOL guess we're fcked..

[oshak]

I actually found it to be an easy or doable paper overall. The only question I struggled with was integrating x+1/x^2+1. Apart from that my main problem was time. I did everything but again not with perfect accuracy.

How about the rest?

[oshak]

By the way, Is it okay if I graphed using pencil on the answer booklet? My friend told me the graph may not get scanned...If so I'm screwed haha :/

[sanadiwan2006]

Terrible paper.

The first question tricked you into thinking it was easy, and then things just get kinda out of hand.

Very, very lengthy- couldn't even read Question 9 and 10.

Although, Section B was fairly easy... so I guess that was an okay compromise.

Also, in one of the arctan x questions you would get arctan 1, which is pi/4

and in the other arctan question you use the formula arctan x + arctan y = arctan (x + y / 1- xy)

(I don't remember the question numbers for both of these arctan questions.

In section B, although the vectors question may seem difficult since it was different from all the papers given, it wasn't necessarily difficult. Skew lines found by equating y and x- but z doesn't equate; and intersection on plane and line (for which we use the cos x formula).

Perhaps I ran out of time because I got really confused in one of the questions- else I can imagine that many must have finished the paper in time.

That being said, after trying almost every past paper from 2008 onwards, this definitely had a different trend to the questions and was difficult because it was very unexpected.

[Vioh]

To be honest, this paper was easier than what i've expected since the mock that I did (the specimen 2014) was super super hard in my opinion. I managed to do all the questions in this paper, but also managed to mess up quite a few. I remember question 10, where we have to integrate using the substitution x=asec(theta). That went horrible, cuz i got the final result that was completely different from the answer. I've probably made some silly mistakes in the calculations

The last question was quite interesting i think. I remembered that we have to find f'(x) first, which i found to be 0. Because of that, f(x) does not change as x increase, thus choosing any x>0 (for example x = 1) would give y = pi/2 because y=arctan(x) + arctan(1/x). Can you guys tell me if this was the correct method?

Also, i messed up the proof (also in the last question) about whether f(x) is even or odd. I claimed that it is odd, because f'(x) is even, because f'(-x)=f'(x)=0, but i never really showed how. So silly of me!!!

Overall it went well, i think. But let's hope that paper 2, and 3 will be much easier than this

Edited May 15, 2014 by Vioh

[Vioh]

Oh, I remember a question.

It had a drawn graph and asked to find stationary points and points of inflexion.

For the stationary points I believe I got x=1±root(2). This didn't correspond with the graph, which seemed to indicate something more like -1±root(2). So I went over the question for a few minutes trying to figure out where I went wrong.

Well, after the exam I graphed the equation, which I believe to have been (x-1)/(x^2+1)

Turns out x=1±root(2) was correct, it was just a different graph that was graphed. I believe it was (x+1)/(x^2+1).

I may be wrong and have read the equation incorrectly, but if this is intentional to mislead students from reading off the graph then that's... bad.

I remember that question as well. I got -1±root(2) which seemed to correspond with the graph as you said. But if it was indeed 1±root(2), then that's really....bad....as the question was worth like 10 points or something.

Edited May 15, 2014 by Vioh

[Jenna26]

I thought it was brutal. So did my classmates. I'm actually quite surprised most of you here thought it was easy. Now i'm scared

[Negotiation]

I got -1±root(2) which seemed to correspond with the graph as you said.

Ah damn... I may just not have realized that I read the equation wrong then. Do you remember if it was (x+1)/(x^2+1)?

[RG_2995]

Yea I thought it waa hard too and I am scared also now

Oh lord bless me!!

[Tinypaws]

I actually found it to be an easy or doable paper overall. The only question I struggled with was integrating x+1/x^2+1. Apart from that my main problem was time. I did everything but again not with perfect accuracy.

How about the rest?

I struggled to integrate that as well! I ended up doing it in the last 5 minutes of the exam. What I did was I separated it the fraction into x/(x²+1) + 1/(x²+1). I integrated x/(x²+1) by substitution of u = x²+1, and 1/(x²+1) was the derivative of arctan(x) as shown in the formula booklet. Hopefully that was correct though...

To be honest, this paper was easier than what i've expected since the mock that I did (the specimen 2014) was super super hard in my opinion. I managed to do all the questions in this paper, but also managed to mess up quite a few. I remember question 10, where we have to integrate using the substitution x=asec(theta). That went horrible, cuz i got the final result that was completely different from the answer. I've probably made some silly mistakes in the calculations

The last question was quite interesting i think. I remembered that we have to find f'(x) first, which i found to be 0. Because of that, f(x) does not change as x increase, thus choosing any x>0 (for example x = 1) would give y = pi/2 because y=arctan(x) + arctan(1/x). Can you guys tell me if this was the correct method?

Also, i messed up the proof (also in the last question) about whether f(x) is even or odd. I claimed that it is odd, because f'(x) is even, because f'(-x)=f'(x)=0, but i never really showed how. So silly of me!!!

Overall it went well, i think. But let's hope that paper 2, and 3 will be much easier than this

For y = arctan(x) + arctan(1/x), I also thought it was odd, because f(-x) = -f(x) as arctan(-x) + arctan(-1/x) = -(arctan(x) + arctan(1/x)). Also I said that it would be -π/2 for x<0. I also agree that the specimen paper 1 was super tricky, I tried doing it the day before the paper 1 exam and I really struggled!

How about the question that asked to find what a² + b² was "without solving the equation"? I got 5, but I'm very unsure as we didn't really talk about sum and products of roots in class!

[fufufuufufufufuuu]

I actually found it to be an easy or doable paper overall. The only question I struggled with was integrating x+1/x^2+1. Apart from that my main problem was time. I did everything but again not with perfect accuracy.

How about the rest?

I struggled to integrate that as well! I ended up doing it in the last 5 minutes of the exam. What I did was I separated it the fraction into x/(x²+1) + 1/(x²+1). I integrated x/(x²+1) by substitution of u = x²+1, and 1/(x²+1) was the derivative of arctan(x) as shown in the formula booklet. Hopefully that was correct though...

To be honest, this paper was easier than what i've expected since the mock that I did (the specimen 2014) was super super hard in my opinion. I managed to do all the questions in this paper, but also managed to mess up quite a few. I remember question 10, where we have to integrate using the substitution x=asec(theta). That went horrible, cuz i got the final result that was completely different from the answer. I've probably made some silly mistakes in the calculations

The last question was quite interesting i think. I remembered that we have to find f'(x) first, which i found to be 0. Because of that, f(x) does not change as x increase, thus choosing any x>0 (for example x = 1) would give y = pi/2 because y=arctan(x) + arctan(1/x). Can you guys tell me if this was the correct method?

Also, i messed up the proof (also in the last question) about whether f(x) is even or odd. I claimed that it is odd, because f'(x) is even, because f'(-x)=f'(x)=0, but i never really showed how. So silly of me!!!

Overall it went well, i think. But let's hope that paper 2, and 3 will be much easier than this

For y = arctan(x) + arctan(1/x), I also thought it was odd, because f(-x) = -f(x) as arctan(-x) + arctan(-1/x) = -(arctan(x) + arctan(1/x)). Also I said that it would be -π/2 for x<0. I also agree that the specimen paper 1 was super tricky, I tried doing it the day before the paper 1 exam and I really struggled!

How about the question that asked to find what a² + b² was "without solving the equation"? I got 5, but I'm very unsure as we didn't really talk about sum and products of roots in class!

for the a^2 + b^2 you just use (a+b)^2 = a^2+ 2ab +b^2, and then to get a^2 + b^2 you just rearrange it to get (a+b)^2- 2ab

everyone just came out from the hall saying it's doable... how high can the grade boundaries go? i need to get at least a 5 O:

[Guest]

The paper was doable except for a few and reaalllly long. I would have liked to check over my work again but no time.

Section B was blllleeaaarggggghhhhhhh

Question 14 was weird as hell. I couldn't do the "show that blah blah is blah blah" questions. But those questions didn't have alot of marks assigned to it though.

Question 10 part (b) I think I messed up because I didn't take into account of the different order the thingies could be chosen in.

The question where you had to do the really nasty differentiation with the horrible polynomial was bad. I got the answer but I couldn't do the next part connected to it to get the points of inflection. I did the integration question after though.

Section A was mostly OK

I think I got some questions wrong but I think I can get partial marks

But overall I think I did decently.

[Dax]

I thought it was hard as well. Messed up a bit, but Section B was amazing I think. Overall not too bad but not good either. I with you guys, I'm scared as well!