# How do you verify #sin x(1- 2 cos ^2 x + cos ^4 x) = sin ^5 x#?

##### 2 Answers

Verify

#### Explanation:

The key to the proof is to factor the left hand side

#### Explanation:

When I see a set of parenthesis I always want to see if it can be factored into a simpler form.

So it turns out that

so our factored form is:

Now I see that we have

notice if we move the cosine to the other side then we have the

same expression.

so let us substitute the

now it is just a matter of simplifying the left hand side.

and thus it is demonstrated.

and that makes us happy.