Question

How do you find the product of `(7u+6v)(7u-6v)`?

Answer 1

`49u^2-36v^2`

Explanation:

In this kind of question, the "middle terms" cancel out, so the first term and final terms multiply:

`(7u+6v)(7u-6v)`

`7uxx7u=49u^2`
`7uxx-6v=-42uv`
`6vxx7u=42uv`
`6vxx-6v=-36v^2`

The middle terms cancel and we're left with:

`49u^2-36v^2`