## College Algebra (6th Edition)

domain : $\{\ x \ |\ \ x\neq-8, \ x\neq 8 \ \}$ interval notation: $(-\infty,-8)\cup(-8,8)\cup(8,\infty)$
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: $x^{2}-64=0\qquad$... recognize a difference of squares $(x-8)(x+8)=0$ $x=8$ or $x=-8\qquad$(zero product principle) domain : $\{\ x \ |\ \ x\neq-8, \ x\neq 8 \ \}$ interval notation: $(-\infty,-8)\cup(-8,8)\cup(8,\infty)$