[tex]\bf a^{-{ n}} \implies \cfrac{1}{a^{ n}}\qquad \qquad
\cfrac{1}{a^{ n}}\implies a^{-{ n}}\\
---------------\\
thus\\
(x+4)^{-1}\implies \cfrac{1}{x+4}
\\\\
[/tex]
[tex]\bf if\qquad \cfrac{1}{0} \implies[/tex] undefined
so.. what value of "x" makes x+4 to 0?
the domain will be, all real numbers, except that value
about the range, "y" will take, whateve "x" can provide.. in this case... I think is all real numbers, except 0, because, if you give a few big values to "x", the fraction will simply have a bigger and bigger denominator, making the fraction smaller and smaller, ever approaching 0, but never getting there
