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Math SL paper 1 TZ2


Surya Tej

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I got 3 seconds and 2/3 as well.

However, the paper was hard in the sense that I managed to make really stupid mistakes and messed up a lot of questions...and the IB won't give you points if you substituted the wrong numbers, but calculated everything right, right? ;(

Most of the marks are actually method marks (there's usually only 1 mark for the answer itself) so if your working was correct then you should get some marks :)

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paper 1 was alright, but I made a lot of bad mistakes. Did a really dumb thing when I forgot that 1/6 is 6^-1. Also the last vector equation was really confusing. The collision happens at whatever position. It asks 'How long does Ryan's airplane take off after Jack's airplane?', but I swear Ryan's plane took off first.....................

Also couldn't figure out how to do the last question to find q. (lnq^2 + 5) - (ln5 + 5) = ln7.

square root 65 seems like a suitable answer.

Just hoping I get a 5, praying to god I get a 6 overall.

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I got 3 seconds and 2/3 as well.

However, the paper was hard in the sense that I managed to make really stupid mistakes and messed up a lot of questions...and the IB won't give you points if you substituted the wrong numbers, but calculated everything right, right? ;(

Well, if you actually did make a mistake, and you showed working, you can get a mark for correct reasoning, as well as the godsend of error carrying. That saved my ass in more than one past paper.

Wow, at least something.

There was this one example and I read off the wrong number and therefore probably calculated everything right, but with the false number. I could seriously just..argghh. This is making me very very angry...that question was like 6 or 7 marks. D:

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The paper was quite good for me, although not sure about the Un question

Did anyone else get square root of 12 on the last question? Heard really varied results on it.

Also does anyone know the positions of the derivatives and f(x) values that we had to place in order from lowest to greatest?

I found square root of 65

I also got root 65 :)

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There was this one question about sequences that im still not sure about. Did guys find the value of k?

hi :) i did that at first, but i realised it wasnt an integer. so basically i dont think you need to. since you had s2 you know that u2 is s2 - u1

did you do that? and what did all of you write for the general expression? i just added the arithmetic sequence with u1=1 d=3 to the geometric one with u1=k r=2 or sth

f(0)<f'(x)<f''(-2). I can't remember what x was for the derivative but I'm very certain that that's the correct answer.

Safe to say, I messed up on that one, my brain wasn't functioning properly then (started with section B).

Ah well, aiming for that 5.

i wrote it the other way around because f''(-2) was negative? since f'(x) was decreasing so i had f(-2)<F'(6)<f(0)

yeah I found d = 3 and k = 0 so u1 = 1

how did u guys know its arithmetic or geometric?

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There was this one question about sequences that im still not sure about. Did guys find the value of k?

hi :) i did that at first, but i realised it wasnt an integer. so basically i dont think you need to. since you had s2 you know that u2 is s2 - u1

did you do that? and what did all of you write for the general expression? i just added the arithmetic sequence with u1=1 d=3 to the geometric one with u1=k r=2 or sth

f(0)<f'(x)<f''(-2). I can't remember what x was for the derivative but I'm very certain that that's the correct answer.

Safe to say, I messed up on that one, my brain wasn't functioning properly then (started with section B).

Ah well, aiming for that 5.

i wrote it the other way around because f''(-2) was negative? since f'(x) was decreasing so i had f(-2)<F'(6)<f(0)

yeah I found d = 3 and k = 0 so u1 = 1

how did u guys know its arithmetic or geometric?

apparently it was both. So you had to use both geometric and arithmetic sequences

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There was this one question about sequences that im still not sure about. Did guys find the value of k?

hi :) i did that at first, but i realised it wasnt an integer. so basically i dont think you need to. since you had s2 you know that u2 is s2 - u1

did you do that? and what did all of you write for the general expression? i just added the arithmetic sequence with u1=1 d=3 to the geometric one with u1=k r=2 or sth

f(0)<f'(x)<f''(-2). I can't remember what x was for the derivative but I'm very certain that that's the correct answer.

Safe to say, I messed up on that one, my brain wasn't functioning properly then (started with section B).

Ah well, aiming for that 5.

i wrote it the other way around because f''(-2) was negative? since f'(x) was decreasing so i had f(-2)<F'(6)<f(0)

yeah I found d = 3 and k = 0 so u1 = 1

how did u guys know its arithmetic or geometric?

apparently it was both. So you had to use both geometric and arithmetic sequences

but you didn't have to find value of anything. In a) you had to basically ubtract S2-S1, then S3-S2 and then S4-S3 and i b) the general formula for any Un had to be given and it was -2+3n + 2^(n-1)*k, but there was nothing about the actual value of k or whether it is arithmetic or geometric sequence;o

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Guest tvfrreak96

There was this one question about sequences that im still not sure about. Did guys find the value of k?

hi :) i did that at first, but i realised it wasnt an integer. so basically i dont think you need to. since you had s2 you know that u2 is s2 - u1

did you do that? and what did all of you write for the general expression? i just added the arithmetic sequence with u1=1 d=3 to the geometric one with u1=k r=2 or sth

f(0)<f'(x)<f''(-2). I can't remember what x was for the derivative but I'm very certain that that's the correct answer.

Safe to say, I messed up on that one, my brain wasn't functioning properly then (started with section B).

Ah well, aiming for that 5.

i wrote it the other way around because f''(-2) was negative? since f'(x) was decreasing so i had f(-2)<F'(6)<f(0)

yeah I found d = 3 and k = 0 so u1 = 1

how did u guys know its arithmetic or geometric?

apparently it was both. So you had to use both geometric and arithmetic sequences

but you didn't have to find value of anything. In a) you had to basically ubtract S2-S1, then S3-S2 and then S4-S3 and i b) the general formula for any Un had to be given and it was -2+3n + 2^(n-1)*k, but there was nothing about the actual value of k or whether it is arithmetic or geometric sequ

Yeah, same here. I am quite positive that we did not have to find the value of k. But I did not get the general formula you got! I didn't realize that it was both arithmetic and geometric. I am scared now, because i honestly thought i was going to ace this exam :S

And in the part (a) of the vector question, was the speed of Ryan's airplane 6? I just took the magnitude of the direction vector.

Also, was it just me, or the least to great function's answer was: f'(6)<f''(-2)<f(0)? Because i clearly remember that f''(-2) also had possible positive values (greater than 0) and also negative values, whereas f'(6) was only 0. I am so confused right now.

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There was this one question about sequences that im still not sure about. Did guys find the value of k?

hi :) i did that at first, but i realised it wasnt an integer. so basically i dont think you need to. since you had s2 you know that u2 is s2 - u1

did you do that? and what did all of you write for the general expression? i just added the arithmetic sequence with u1=1 d=3 to the geometric one with u1=k r=2 or sth

f(0)<f'(x)<f''(-2). I can't remember what x was for the derivative but I'm very certain that that's the correct answer.

Safe to say, I messed up on that one, my brain wasn't functioning properly then (started with section B).

Ah well, aiming for that 5.

i wrote it the other way around because f''(-2) was negative? since f'(x) was decreasing so i had f(-2)<F'(6)<f(0)

yeah I found d = 3 and k = 0 so u1 = 1

how did u guys know its arithmetic or geometric?

apparently it was both. So you had to use both geometric and arithmetic sequences

but you didn't have to find value of anything. In a) you had to basically ubtract S2-S1, then S3-S2 and then S4-S3 and i b) the general formula for any Un had to be given and it was -2+3n + 2^(n-1)*k, but there was nothing about the actual value of k or whether it is arithmetic or geometric sequ

Yeah, same here. I am quite positive that we did not have to find the value of k. But I did not get the general formula you got! I didn't realize that it was both arithmetic and geometric. I am scared now, because i honestly thought i was going to ace this exam :S

And in the part (a) of the vector question, was the speed of Ryan's airplane 6? I just took the magnitude of the direction vector.

Also, was it just me, or the least to great function's answer was: f'(6)<f''(-2)<f(0)? Because i clearly remember that f''(-2) also had possible positive values (greater than 0) and also negative values, whereas f'(6) was only 0. I am so confused right now.

Hahhahahhahaha ah that Un question -.-

and yeah I also got 6 , for the function one, I think the f"(-2) can only be negative since it concave down?

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There was this one question about sequences that im still not sure about. Did guys find the value of k?

hi :) i did that at first, but i realised it wasnt an integer. so basically i dont think you need to. since you had s2 you know that u2 is s2 - u1

did you do that? and what did all of you write for the general expression? i just added the arithmetic sequence with u1=1 d=3 to the geometric one with u1=k r=2 or sth

f(0)<f'(x)<f''(-2). I can't remember what x was for the derivative but I'm very certain that that's the correct answer.

Safe to say, I messed up on that one, my brain wasn't functioning properly then (started with section B).

Ah well, aiming for that 5.

i wrote it the other way around because f''(-2) was negative? since f'(x) was decreasing so i had f(-2)<F'(6)<f(0)

yeah I found d = 3 and k = 0 so u1 = 1

how did u guys know its arithmetic or geometric?

apparently it was both. So you had to use both geometric and arithmetic sequences

but you didn't have to find value of anything. In a) you had to basically ubtract S2-S1, then S3-S2 and then S4-S3 and i b) the general formula for any Un had to be given and it was -2+3n + 2^(n-1)*k, but there was nothing about the actual value of k or whether it is arithmetic or geometric sequ

Yeah, same here. I am quite positive that we did not have to find the value of k. But I did not get the general formula you got! I didn't realize that it was both arithmetic and geometric. I am scared now, because i honestly thought i was going to ace this exam :S

And in the part (a) of the vector question, was the speed of Ryan's airplane 6? I just took the magnitude of the direction vector.

Also, was it just me, or the least to great function's answer was: f'(6)<f''(-2)<f(0)? Because i clearly remember that f''(-2) also had possible positive values (greater than 0) and also negative values, whereas f'(6) was only 0. I am so confused right now.

Hahhahahhahaha ah that Un question -.-

and yeah I also got 6 , for the function one, I think the f"(-2) can only be negative since it concave down?

I got the answer that f''(-2)<f'(6)<f(0), as at -2, there was maximum of the function so second derivative must be negative, at 6 there was min and so stationary point which for first derivative is always 0 and f(0) was intersection y-axis at ome value above 0 so it was positive

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There was this one question about sequences that im still not sure about. Did guys find the value of k?

hi :) i did that at first, but i realised it wasnt an integer. so basically i dont think you need to. since you had s2 you know that u2 is s2 - u1

did you do that? and what did all of you write for the general expression? i just added the arithmetic sequence with u1=1 d=3 to the geometric one with u1=k r=2 or sth

f(0)<f'(x)<f''(-2). I can't remember what x was for the derivative but I'm very certain that that's the correct answer.

Safe to say, I messed up on that one, my brain wasn't functioning properly then (started with section B).

Ah well, aiming for that 5.

i wrote it the other way around because f''(-2) was negative? since f'(x) was decreasing so i had f(-2)<F'(6)<f(0)

I figured out an expression for Un in the sequence. I said something like… Un=(1+K)+3(n-1)+(K x 2n-1)-K ... Very well could have been wrong… Kind of like what you were saying with an arithmetic and geometric expression hybrid… :)

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Did anyone else get square root of 12 on the last question? Heard really varied results on it.

Also does anyone know the positions of the derivatives and f(x) values that we had to place in order from lowest to greatest?

I found square root of 65

I got root 12 too. I checked it a few times, I remember coming out confident of that last question

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  • 5 weeks later...

As someone who was predicted a 3 - 4 for Maths SL and spent four solid days revising for just Maths, I felt that the Paper went really, really well. I was so happy with the vectors question, it's one of the easiest topics for me to do, ahhhh~ :D I thought paper 2 went really well too, though I was an idiot and forgot how to use the graphics calculator halfway through the exam and panicked a little bit :S Otherwise, it's a bit of a stretch but I'm crossing my fingers for a 5 or maybe even a 6 after those papers, especially since I got pretty good predicted grade for the Maths IA (which I HATE THAT THEY CHANGED THIS YEAR, WHY)

 

All in all, fingers crossed guys, our journey's over :D

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Guest Daniel Augusto

 

 

 

 

 

There was this one question about sequences that im still not sure about. Did guys find the value of k?

 

hi :) i did that at first, but i realised it wasnt an integer. so basically i dont think you need to. since you had s2 you know that u2 is s2 - u1 

 

did you do that? and what did all of you write for the general expression? i just added the arithmetic sequence with u1=1 d=3 to the geometric one with u1=k r=2 or sth

 

 

 

f(0)<f'(x)<f''(-2). I can't remember what x was for the derivative but I'm very certain that that's the correct answer. 

Safe to say, I messed up on that one, my brain wasn't functioning properly then (started with section B). 

Ah well, aiming for that 5. 

 

 

i wrote it the other way around because f''(-2) was negative? since f'(x) was decreasing so i had f(-2)<F'(6)<f(0)

 

yeah I found d = 3 and k = 0 so u1 = 1

 

how did u guys know its arithmetic or geometric?

 

apparently it was both. So you had to use both geometric and arithmetic sequences

 

but you didn't have to find value of anything. In a) you had to basically ubtract S2-S1, then S3-S2 and then S4-S3 and i b) the general formula for any Un had to be given and it was -2+3n + 2^(n-1)*k, but there was nothing about the actual value of k or whether it is arithmetic or geometric sequence;o

 

Pretty sure my final expression was similar, however if I remember correctly... it was 1 + k, 3 + 2k, 5 + 4k, 7 + 8k and so on, giving Un = (2n-1) + 2^(n-1)*k

I might have actually put (3n - 1) isntead of (2n-1) or something like that accidentally :S I hope I only lose 1 mark from this question... assuming everything else is correct LOL

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