Answer
domain : $\{\ x \ |\ \ x\neq-7, \ x\neq 7 \ \}$
interval notation: $(-\infty,-7)\cup(-7,7)\cup(7,\infty)$
Work Step by Step
See example 1.
Division by 0 is undefined, so
$h(x)$ will be defined for all real numbers except for
the number(s) x that yield zero in the denominator:
$ x^{2}-49=0\qquad$... recognize a difference of squares
$(x-7)(x+7)=0$
$x=7$ or $x=-7\qquad $(zero product principle)
domain : $\{\ x \ |\ \ x\neq-7, \ x\neq 7 \ \}$
interval notation: $(-\infty,-7)\cup(-7,7)\cup(7,\infty)$
