Sign of Odd Power/Corollary

Corollary to Sign of Odd Power
Let $x \in \R$ be a real number. Let $n \in \Z$ be an odd integer.

Then:
 * $\paren {-x}^n = -\paren {x^n}$

Proof
We have:
 * $\size {-x}^n = \size {-\paren {x^n} }$

and the result follows from Sign of Odd Power.