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# Vector Proof questions watch

1. Hey can anyone help me answer this question, 5 marks
2. Infact don't worry I know how to solve it.

The vector AR can be found in two different ways in which they are both equal in each other, therefore I can re-arrange for r

Spoiler:
Show

Correct me if I'm wrong tho
3. Since R divides AB into the ration m:n, . Then rearrange to find r
4. (Original post by CraigBackner)
Infact don't worry I know how to solve it.

The vector AR can be found in two different ways in which they are both equal in each other, therefore I can re-arrange for r

Spoiler:
Show

Correct me if I'm wrong tho

I don't think that will work. since the vectors when you find AR in the other way will cancel to leave your original AR
5. (Original post by h3rmit)
Since R divides AB into the ration m:n, . Then rearrange to find r
should't the equation be ?
6. (Original post by CraigBackner)
should't the equation be ?
Yes, and that's what I typed first time correctly with 100% definitely no mistakes.
7. h3rmit is correct although

edit: im so confused with edits
8. (Original post by h3rmit)
I don't think that will work. since the vectors when you find AR in the other way will cancel to leave your original AR
The vector AR is r-a and the second vector is which equals

when these two are equal and you rearange for r you get

which is the given expression
9. (Original post by CraigBackner)
The vector AR is r-a and the second vector is (m)/(m+n)(AB) which equals (mb-ma)/(m+n)

when these two are equal and you rearange for r you get (bm+an)/(m+n)

which is the given expression
Ah, I thought you meant using the triangle and a, r, and b only
10. It's not even a proof question but a show me

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