OCR M1 - 31st May 2012 :)

help me out on the one im stuck on please i linked it above

http://www.xtremepapers.com/papers/OCR/Maths/2006%20Jun/M1.pdf

question 3ii..

i get s = 2.25t for respect to the woman.
i get that the answer is inbetween 80 and 120.

how do i set up this other equation, i have u+v are both 4.5, and t = t. a is both 0 for both?
any help?

this one

ill have a look

Can someone explain to me what part ii) of this question is asking and tell me how to do it?

http://d.pr/i/dZFu

go back a few pages, it was asked before

it's almost as if it's too easy. god damn it!

Can you quote the answer, since i too want to know, and cba to check back a few pages.... pweaaase?

literally page 18. lol, there's a whole discussion, not really an answer?

I think it's the same question O.o

it's almost as if it's too easy. god damn it!

have you got it?

im still stuck on it

Nope. I don't understand it,

We are trying to find 2 equations that = S right?
I get S = 2.25t for the man
and for the woman, she goes 4.5ms right? so i thought it would be something like

2.25t = 4.5t + 40

corrong.

it's quite simple, you just need to model each displacement and equate it.

From the diagram it should be obvious that the man over takes the woman during his sprint so we only need to model up to this point.

For the woman, her displacement is constant = 2.25t
For the man, in the first 80 seconds his displacement is 120, then his displacement is (t-80)*4.5 (standard rule of displacement = speed * time)

So Woman Displacement = 2.25
Man Displacement = 120 + 4.5(t-80)

Now equate, 120+4.5(t-80) = 2.25t

Then solve for t which is 106.666666... which seems about right in the diagram.

it's quite simple, you just need to model each displacement and equate it.

From the diagram it should be obvious that the man over takes the woman during his sprint so we only need to model up to this point.

For the woman, her displacement is constant = 2.25t
For the man, in the first 80 seconds his displacement is 120, then his displacement is (t-80)*4.5 (standard rule of displacement = speed * time)

So Woman Displacement = 2.25
Man Displacement = 120 + 4.5(t-80)

Now equate, 120+4.5(t-80) = 2.25t

Then solve for t which is 106.666666... which seems about right in the diagram.

simple question.

is cos(90-a) identical to -sin(a)

?


please help.

simple question.

is cos(90-a) identical to -sin(a)

?


please help.

cos(90-a) is equal to sin(a)

i think i know the question you're doing.

cos(90-a) = sin(a)

You own a calculator right?