May 2014 Math HL Calculus Option

[Semin Park]

How was it?

For me it went absolutely horrendously. Lost 25 marks minimum, and I hope that I got the rest 100% correct.

I was scoring 90% on almost all past papers and didn't really look into the new stuff like the Rolle's Theorem and such. Was a big mistake. Math was one of the surefire subject to get a 7 in, but now I'm looking for a 6.

If I score 80%+ for both P1,P2, then I still could have a chance of getting a 7, but overall, P3 Calculus was absolutely terrible.

I couldn't do the improper integral in the last part of Q1, then panicked and couldn't do another 12 mark question in number 2, where you had to use the integrating factor to do other stuff. The whole thing was linked so when I failed to obtain the IF, I screwed it up.

Q3 was fine, but Q4, I missed the Rolle's theorem part. It was 6-8 marks I think.

Overall this was the only paper so far that shocked me this much, if at all. My whole IB was going very well and now Math is trying to **** me over.

[OctoPauly]

Me and my classmates thought it was one of the easier papers really. I messed up the last bit of Q1 and didn't have time to finish the Rolle's theorem bit of Q4, but 2 and 3 were very standard questions, as was the most of 1 and the continuity/differentiability bit of 4. There were no really obscure questions which I was so relieved about

[sanadiwan2006]

Didn't have time to finish Question 3 (I did 4 first), but otherwise it seemed like a very easy paper- (and really, I'm not the brightest student- but was a very average paper for even me).

[elena-14]

I messed up the paper too.

Q1 was fine, but somehow I couldn't get the integral factor in Q2 and lost all the marks.

I literally took three pages to integrate and then failed.

Q3 went fine but I didn't understand what Q4 was asking, so I lost marks there too.

How on earth do you find a and b so that the function is continuous??

will getting half of the things correct give me a 5??

I preferred the past papers more than this one.

I think they were easier...

[Chuchu1224]

This was by far the easiest of all the papers. I LOVED it. Nothing unfamiliar, nothing unexpected, and plenty of time to finish it. There was not a single tricky part to it, and I am surprised that you found it tough if you had no trouble with papers 1 and 2, which were a lot more difficult.

Why didn't you look into Rolle's theorem? And how couldn't you do the improper integral? Or radius of convergence? This was all standard stuff!

[Freud]

I messed up the paper too.

Q1 was fine, but somehow I couldn't get the integral factor in Q2 and lost all the marks.

I literally took three pages to integrate and then failed.

Q3 went fine but I didn't understand what Q4 was asking, so I lost marks there too.

How on earth do you find a and b so that the function is continuous??

will getting half of the things correct give me a 5??

I preferred the past papers more than this one.

I think they were easier...

For Q4: For the function to be continous, the limits as x approaches 2 must be equal from both sides. Same with the derivatives.

[Guest Eman Salem]

I screwed up question 3 and 4

I spent too much time on question 3, and somehow couldnt find the ratio even though i knew exaclty what had to be done int he rest

question 4 i just hope i get marks for knowing the concept..

[Dudu4322]

It was a pretty decent paper. I only didn't manage to do the improper integral and finish the Rolle's theroem. I wrote something like that the first derivative equals zero twice in the domain, etc. maybe I'll get some points for that. But I spent like 5 minutues trying to find b(n) and c(n) in Q3 and without that I couldn't continue the question. Fortunately I finally found it and just in time to finish the whole question in the time limit ; )

[Dotty]

I think it was a bit over the average, but i just did fine. The only thing i left was the last part of Q4 for Rolle's theorem (didn't study it much, damn it!). How much did you find for the improper integral in Q1? I think i found 1 or something similar.

[jo-david]

I was shocked to see the Rolle's theorem question, but managed to do it anyway haha but I couldn't finish the very last part, where i had to prove the equation had 2 zeros. Also, for the interval of the convergence, I proved that the lower radius was convergent, but didn't know how to test the convergence for the upper radius. So I hope I still get like a third of the whole marks in that part. Overall, I'm expecting about 50/60.

Time managing wasn't as hard as I experienced in p1 and p2

[Guest Lognarithm]

I had NO idea what was going on with the integrating factor and couldn't seem to get the final form from the DQ, but I managed to spit something out about the coordinates using the result they gave in the next part. Also, seriously Rolle's theorem? I drew some graphs basically. There have been much better papers.

[Semin Park]

I just practiced past papers, and that's where I lost all for the Rolle's Theorem marks.

With hindsight, it's entirely my mistake that I couldn't do Q2. I guess I was panicking too much at that point.

From my calculation, if I get 80% in both P1 and P2, I can overall safely achieve 75% overall, so I hope that P1 and P2 would save me..

[elaifyanre]

Just out of curiosity (and fear for the upcoming FM exams), what's the improper integral question you are talking about?

[plshelpme123]

what did you guys get for the integrating factor? also, for the interval question, did y ou guys get converge or diverge for the end points?

[Tinypaws]

Just out of curiosity (and fear for the upcoming FM exams), what's the improper integral question you are talking about?

Question 1 was basically where f(x) = (e^x + e^-x) / 2 ) and g(x) = (e^x - e^-x )/ 2. They tell you that f'(x) = g(x) and g'(x) = f(x). Basically it asked to integrate (from zero to infinity) g(x) / ( f(x) )². Basically you just needed to substitute u = f(x), thus du/dx = g(x) and dx = du/g(x). The g(x) cancels out and you just needed to integrate 1/(u²). Solution on Wolfram Alpha.

what did you guys get for the integrating factor? also, for the interval question, did y ou guys get converge or diverge for the end points?

I got (lnx)² for the integrating factor.

I said that the interval of convergence was -1 ≤ x ≤ 1. Solution on wolfram alpha.

Edited May 18, 2014 by Tinypaws

[Dax]

I got Interval to be Convergent for +1, divergent for -1

[Chuchu1224]

Just out of curiosity (and fear for the upcoming FM exams), what's the improper integral question you are talking about?

Question 1 was basically where f(x) = (e^x + e^-x) / 2 ) and g(x) = (e^x - e^-x )/ 2. They tell you that f'(x) = g(x) and g'(x) = f(x). Basically it asked to integrate (from zero to infinity) g(x) / ( f(x) )². Basically you just needed to substitute u = f(x), thus du/dx = g(x) and dx = du/g(x). The g(x) cancels out and you just needed to integrate 1/(u²). Solution on Wolfram Alpha.

what did you guys get for the integrating factor? also, for the interval question, did y ou guys get converge or diverge for the end points?

I got (lnx)² for the integrating factor.

I said that the interval of convergence was -1 ≤ x ≤ 1. Solution on wolfram alpha.

I got that integrating factor too! And I got that radius of convergence too!

Did you also get 1 for the improper integral?

I got Interval to be Convergent for +1, divergent for -1

That is wrong. It was definitely convergent for both values.

[Tinypaws]

I got that integrating factor too! And I got that radius of convergence too!

Did you also get 1 for the improper integral?

I got Interval to be Convergent for +1, divergent for -1

That is wrong. It was definitely convergent for both values.

Yup, I also got 1 for the improper integral! I also got convergent for both values

[maroctam]

Just out of curiosity (and fear for the upcoming FM exams), what's the improper integral question you are talking about?

Question 1 was basically where f(x) = (e^x + e^-x) / 2 ) and g(x) = (e^x - e^-x )/ 2. They tell you that f'(x) = g(x) and g'(x) = f(x). Basically it asked to integrate (from zero to infinity) g(x) / ( f(x) )². Basically you just needed to substitute u = f(x), thus du/dx = g(x) and dx = du/g(x). The g(x) cancels out and you just needed to integrate 1/(u²). Solution on Wolfram Alpha.

what did you guys get for the integrating factor? also, for the interval question, did y ou guys get converge or diverge for the end points?

I got (lnx)² for the integrating factor.

I said that the interval of convergence was -1 ≤ x ≤ 1. Solution on wolfram alpha.

Looking at your wolfram entry for the interval of convergence, I'm starting to harbour doubt. Wasn't the general term ? This is because it was the sum from n=0 to infinity, and as far as I remember the terms started with 4*5 in the denominator. I'm not sure though, but I'll ask my math teacher whenever I see him as he's an examiner. I know that was only 2 points, but it's two points that I need considering how I feel about papers 1 and 2.