The Student Room Group

OCR MEI C3 Mathematics June 2016 - Official Thread

Scroll to see replies

Original post by klefki
IMG_1929.JPG

I got 55/12 for the area in q8, can someone tell me where I went wrong please? (sorry it's sideways)



8*3=24 not 27
Original post by klefki
IMG_1929.JPG

I got 55/12 for the area in q8, can someone tell me where I went wrong please? (sorry it's sideways)

uno where u got 5/3 i got 14/3
Original post by betapro
No it was just 8 i got that


Yeah I've realised I was on about q5
Reply 183
Avatar for klefki
klefki
3
Original post by sonron202
8*3=24 not 27


oh my god I'm an idiot ahahaha, hopefully only one or two marks for that
Original post by klefki
IMG_1929.JPG

I got 55/12 for the area in q8, can someone tell me where I went wrong please? (sorry it's sideways)


5th equal sign, 2/3(27) = 18 not 9 and 2/3(8) = 16/3 not 8/3 as well as what was said above
Guys help me about question 3 with the modulus question i got x=-1/3 and -1 but i wrote just in case i need y and also put y values will i still get full marks since that is just some extra info?
Anyone remember what we had to integrate for question 1?
Reply 187
Avatar for klefki
klefki
3
Original post by ComputerMaths97
5th equal sign, 2/3(27) = 18 not 9 and 2/3(8) = 16/3 not 8/3


I can't believe out of that entire paper the mistake I made was multiplication :angry:
For the proof I said because n was a positive integer smallest value of 2^n + 1 is 3, as n increases 2^n + 1 or 2^n -1 must be a multiple of 3 ( they alternate each time n increases by 1), therefore if one of the factors is a multiple of 3 the whole equation must be divisible by 3
Original post by Bealzibub
Anyone remember what we had to integrate for question 1?


1 + cos(x/2) I think
Guys for the height question and volume for the first one, once you get 8 did you put units? I put 8 m^2 is that right, if not will ig et marked down?
The proof question:

x^2n - 1 = (x^n - 1)(x^n + 1)
When x = 2
=>2^2n - 1 = (2^n - 1)(2^n + 1)

2^n only has a prime factor of 2, meaning it is not divisible by 3.

Additionally, since, for any 3 consecutive numbers, one of them must be divisible by three (since every 3rd number is a multiple of three)

We can conclude that either 2^n - 1 OR 2^n OR 2^n + 1 is divisible by 3.

Since we have proven 2^n is not divisible by 3.

Either 2^n - 1 or 2^n + 1 must be divisible by 3

Meaning (2^n - 1)(2^n + 1) = 2^2n - 1 is always divisible by 3, as required.
Original post by Bealzibub
Beautiful paper, 71/72 for me, lowest 68/72
This is what I remember:

Unparseable latex formula:

x^2n - 1\\[br](x^n - 1)(x^n + 1)



Odd * odd = odd so divisible by 3

Area = 19/12
ak+b = k-1
4ln(4)-4
Y=(1/2)x
Gradient = 8 question 3
dr/dt = 0.05 m per minute question 3ii
P=(-4, -2)
x = ln2 question 2
x=-1 and x=-1/3
dy/dx=1/(2cos2y)


Ehy are people gettibg k-1 im dead sure its 0.5k -0.5IMG_20160621_115223.jpg
Original post by betapro
Guys for the height question and volume for the first one, once you get 8 did you put units? I put 8 m^2 is that right, if not will ig et marked down?


No because it was a rate without a time variable. meters cubed per meter is not meters^2, it doesn't quite work like that in real life from what I know.

But maybe.
For the area question I left it as 6.25 - 14/3 rather than put 19/12 will I still get all the marks?
Original post by Maligaha
Ehy are people gettibg k-1 im dead sure its 0.5k -0.5IMG_20160621_115223.jpg

You've subbed in the wrong value for X, it said from 1/2lnk
Original post by Maligaha
It looks like you have....


I know I didn't do that, I'd check over your maths as most people seem to have k-1 as the answer
Original post by mrk1357
11*13=143

143 is not divisible by 3

so odd*odd=odd but isnt necessarily divisible by 3


It had to be in the form 2^n-1, 2^n+1. 11 and 13 cannot be expressed in that form
How the hell did you do question 1? Integrating 1+cos1/2x or something.

Is 1+cosx an identity?

Posted from TSR Mobile
(edited 7 years ago)
How did you solve the y intercept for e^2x+ke^(-2x)=0?

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you