Definition: A function of the form $x^{-k}=\frac{1}{x^k}$, with $k$ a non-negative integer, is called a negative integer power function.
Extra explanation 1: Since it is not allowed to divide by zero, $x=0$ is not an element of the domain of this function.
Extra explanation 2: A negative integer power function has no zeros.
Extra explanation 1: Since it is not allowed to divide by zero, $x=0$ is not an element of the domain of this function.
Extra explanation 2: A negative integer power function has no zeros.