Edexcel FP2 Official 2016 Exam Thread - 8th June 2016

Hi guys. Hope everything is going smooth and well. I Have a little problem. I am a self taught student. currently doing past papers and very happy with results. the problem is that the notation i use is different to the markscheme slightly. but i get the same answer as them. will this affect the way im graded?

I got this, am I missing something blindly obvious?

I would think so.

Remember that $a(b+c) = ab + ac \neq ab + c$.

So $\displaystyle \dfrac{3}{2}\left[- \dfrac{1}{3}\cos3x + cosx \right] = \frac{3}{2} \times \frac{-1}{3} \cos 3x + \frac{3}{2} \times \cos x$

so $ysinx = -\dfrac{1}{2} cos3x + \dfrac{3}{2} cosx$

$\therefore ysinx = \dfrac{3cosx-cos3x}{2}$

$\therefore y = \dfrac{3cosx-cos3x}{2sinx}$

That's what I did

Ah, sorry - I misread. Yes, that's fine - the markscheme is in error.

No problem, thank you.

Quite scary how there's a mistake in a 2015 paper's mark scheme.
One can only assume, and hope, that it was fixed in time so candidates weren't marked down

Most likely not - can you give us a few concrete examples of differences in your notation?

So i know this is an fp2 thread but with m3. instead of writing v dv/dx = .... i just write a= ..... and then below straight to 0.5v^2.

Please could anyone explain exercise A question 7a https://8fd9eafbb84fdb32c73d8e44d980d7008581d86e.googledrive.com/host/0B1ZiqBksUHNYTnpyeF8xQlZweHc/CH6.pdf I really can't follow the working! Thanks

What's confusing you?

$\displaystyle \frac{d}{dx}(\ln (x + \sqrt{1+x^2}) = \frac{\frac{d}{d}x(x + \sqrt{1+x^2})}{x + \sqrt{1+x^2}} = \frac{1 + \frac{2x}{2x\sqrt{1+x^2}}}{x + \sqrt{1+x^2}}$

Simplify that down to $\frac{1}{\sqrt{1+x^2}}$ yourself.

Then $f'(x) = \frac{1}{\sqrt{1+x^2}} \iff \sqrt{1+x^2}f'(x) = 1$

Thanks, I think it's the differential of root (1+x squared) that I'm getting wrong, please could you explain how you do it? I got x(1+x squared)^-0.5, as the differential for it :/ thank you

Thanks, understand that now, how does the expression simplify down please as I have 1+ x/root( 1+x^2) divided by x+root(1+x^2) but I can't seem to simplify it. Thanks

Thanks, understand that now, how does the expression simplify down please as I have 1+ x/root( 1+x^2) divided by x+root(1+x^2) but I can't seem to simplify it. Thanks

Hi guys, need a little help with a method of differences question if that's okay. The partial fractions gives three terms and I wrote down the expansion (I did this correctly as I checked it against the mark scheme), however I saw no pattern in cancelling out the terms. What is the protocol for going about this when there are three terms instead of 2?

I have linked the mark scheme's expansion.

See if any of this makes sense to you. It can be hard to see what to do, but if the result is given, you can try and 'force it'.
Thank you and thanks @Zacken
Oops, didn't realize Zacken was online...