Question

derivative of f(x)=8/x at x=-1

Answer 1

Do you know how to solve derivatives?

Answer 2

yes. I got the answer 8/x^2. But I'm not sure if it should be negative or not.

Answer 3

how do you find your derivatives? limit rules or derivative shortcuts?

Answer 4

I used difference quotient.

Answer 5

then your application of it was slightly off

Answer 6

I know the answer is going to be 8 or -8 but I'm not sure which one.

Answer 7

\[\frac{x(8')-8(x')}{x^2}\]
\[\frac{x(0)-8(1)}{x^2}\]
\[\frac{-8}{x^2}\]
now apply x=-1

Answer 8

Okay, so the answer is 8?

Answer 9

no, (-1)^2 = 1 and -8/1 = -8

Answer 10

surely -8

Answer 11

my mistake, -8 for sure lol. Thank you amistre64!

Answer 12

;) good luck, its the algebra thats a killer lol