Question

Find the derivative of f(x) = negative 9 divided by x at x = -8.

Answer 1

`f'(-8)=(9)/(64)`

Explanation:

Given the function

`f(x)=(-9)/(x)`

We can rewrite it as

`f(x)=-9x^(-1)`

Now we can apply the power rule

`f'(x)=9x^(-2)`

Now we can rewrite it

`f'(x)=(9)/(x^(2) )`

Now we can plug in x=-8

`f'(-8)=(9)/((-8)^(2) )\\f'(-8)=(9)/(64)`