Mr M's OCR (not OCR MEI) Further Pure 1 answers May 2017
(ii) 18 and 207π (5 marks)
(iii) Perpendicular bisector of line segment joining z1 and z2 (2 marks)
for part ii arg(z1) = 3pi/5, arg(z2) = -9pi/10, |z1|=|z2|=3, wouldn't that mean the angle between them is pi/2 thus making the arg(z1-z2) = 17pi/20 not 7pi/20
for part ii arg(z1) = 3pi/5, arg(z2) = -9pi/10, |z1|=|z2|=3, wouldn't that mean the angle between them is pi/2 thus making the arg(z1-z2) = 17pi/20 not 7pi/20
unless i remember/read the question differently
Angle between them is pi/2, you are correct. However, arg(z1-z2) is 7pi/20. There is a diagram on the previous (I think) page which shows what z1-z2 looks like and you'll so it is around 7pi/20. If not, I could write a proof/show an answer.
for part ii arg(z1) = 3pi/5, arg(z2) = -9pi/10, |z1|=|z2|=3, wouldn't that mean the angle between them is pi/2 thus making the arg(z1-z2) = 17pi/20 not 7pi/20
Something along the lines of that I would imagine. Not 6 marks of work imo though, so just a guess.
Do you think I'd get 3 out of 6 for getting 2b=d and also rearranging a bunch of other stuff but somehow managing to get a cube root? It was quite close to the answer btw - i think a cube root instead of a square root or something similar - also forgot a plus/minus.
Do you think I'd get 3 out of 6 for getting 2b=d and also rearranging a bunch of other stuff but somehow managing to get a cube root? It was quite close to the answer btw - i think a cube root instead of a square root or something similar.
Will really heavily depend on the markscheme. Not easy to tell. You might, you might not. You might get 3/6 for getting d = 2b outright, you might just get 1 for it. Sorry I can't help more :/
EDIT: Forgetting +/- might not do anything to your mark as you got something different, but there might be a whole mark for putting +/-. Again, sorry I can't help more!
Will really heavily depend on the markscheme. Not easy to tell. You might, you might not. You might get 3/6 for getting d = 2b outright, you might just get 1 for it. Sorry I can't help more :/
EDIT: Forgetting +/- might not do anything to your mark as you got something different, but there might be a whole mark for putting +/-. Again, sorry I can't help more!
That's fine, thanks. I think it'll be around 56/57 for an A.
That's fine, thanks. I think it'll be around 56/57 for an A.
Honestly no idea to be honest. I got like 64-66 just cos I'm bad at exams tbh :/ Seemed easier than last year's paper to me, but I've had another year so Idk. We'll see.
Honestly no idea to be honest. I got like 64-66 just cos I'm bad at exams tbh :/ Seemed easier than last year's paper to me, but I've had another year so Idk. We'll see.
I feel really thick, for the 3x3 matrix one i got two values for a, one being 5 and the other being 2, will i lose marks for this? Really wasn't my exam today :/