# Problem involving dot and cross product

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1. Jul 31, 2015

### matthew1

1. The problem statement, all variables and given/known data

https://www.dropbox.com/s/8l90hahznjlv9d0/vector problem.png?dl=0

2. Relevant equations

Dot and Cross product

3. The attempt at a solution

although I know the dot and cross product, I'm not sure what I'm being asked or how to proceed? any help?

2. Jul 31, 2015

### Student100

Have you tried to turn it into a concrete example than generalizing it?

The problem wants you to find a dot b and a cross b then use them to show the equation for a.

Last edited: Jul 31, 2015
3. Aug 1, 2015

### haruspex

In (a), take the dot product with $\vec a$ on each side of the given equation. What equation results? Then get that equation into the form $\vec a.\vec b =$.