Question

How do you find the domain for `f(x)=(x+5)/(x^2-25)`?

Answer 1

The Domain of `f` is `RR-{+-5}`.

Explanation:

As division by Zero is not allowed, we must have, `x^2-25!=0`.

As, `x^2-25=0 rArr (x-5)(x+5)=0 rArr x=+-5`

`:. x62-25!=0 rArr x!=+-5`.

Hence, the Domain of `f` is `RR-{+-5}`.