Question

find f(x) for f(x)= - 9x^7. f(x)=□

Explanation:

Step1: Recall power - rule for differentiation

The power - rule states that if $y = ax^n$, then $y^\prime=anx^{n - 1}$, where $a$ is a constant and $n$ is a real number.
For the function $f(x)=-9x^7$, $a=-9$ and $n = 7$.

Step2: Apply the power - rule

$f^\prime(x)=(-9)\times7x^{7 - 1}$.
$f^\prime(x)=-63x^6$.

Answer:

$-63x^6$