# Need help with grade 12 vectors (basic question) and a calc question about a curve

• Sep 21st 2011, 07:04 PM
cngcngcng
Need help with grade 12 vectors (basic question) and a calc question about a curve
Hi everyone, I am new here.
I am having trouble with question 3 and 8, 9 the most. But I pretty much don't get all of it, I would really appreciate your help,

Christy
• Sep 21st 2011, 07:13 PM
pickslides
Re: Need help with grade 12 vectors (basic question) and a calc question about a cur
I can help, what have you done to answer these?
• Sep 21st 2011, 07:19 PM
cngcngcng
Re: Need help with grade 12 vectors (basic question) and a calc question about a cur
Hi! I've done this so far:
• Sep 21st 2011, 07:21 PM
cngcngcng
Re: Need help with grade 12 vectors (basic question) and a calc question about a cur
As well as this:

9. v can be broken down to y = sin40 x 5 and x = –cos 40 x 5

w can be broken down to y = 2 sin55 and x = 2 cos 55

now we want to replicate w, to match y, 5 sin40 / 2 sin 55 = 0.5 of v is needed

to match x, (2 cos 55 + 5cos 40 )/4 = 1.24 of u is needed (but in the opposite direction tho),

so w = 0.5 v -1.24 u

But I had help from my friend who can skip steps really quickly and so what I really want to know is the steps...:)