Problem involving dot and cross product

[matthew1]

Homework Statement

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

Homework Equations

Dot and Cross product

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?[/B]

 

[Student100]

Homework Statement

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

Homework Equations

Dot and Cross product

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?[/B]

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.

 

[haruspex]

Do as the steps ask.
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 $\vec a.\vec b =$.

The note at the end has a typo. Are you familiar with the equation that was intended?