Question

What is the range of the function `h(x) = 1 /(x^2 - 9)`?

Answer 1

`y\geq -1/9`, `yne 0`

Explanation:

`y` is in the range if and only if the polynomial `p(x)=yx^2-y9-1=0` has a root, and it has a root if and only if `9+1/ygeq 0` and `yne 0`, so
`y\geq -1/9`, `yne 0`