SOLUTION: PLEASE HELP!! have tried but my teacher said it was incorrect Use the definition of the derivative (that is, do not use rules) to find the derivative of the function z=-2/-x^2

Algebra ->  Complex Numbers Imaginary Numbers Solvers and Lesson -> SOLUTION: PLEASE HELP!! have tried but my teacher said it was incorrect Use the definition of the derivative (that is, do not use rules) to find the derivative of the function z=-2/-x^2      Log On


   

Question 968385: PLEASE HELP!! have tried but my teacher said it was incorrect
Use the definition of the derivative (that is, do not use rules) to find the derivative of the function
z=-2/-x^2
with respect to x.
Answer by josgarithmetic(39613) About Me  (Show Source):
You can put this solution on YOUR website!
That must mean to use the difference quotient, pick your variable to be the infinitessimal number to approach zero.

z=-2%2F%28-x%5E2%29, is same as z=2%2Fx%5E2. No sense trying to avoid that initial simplification .

You use a new variable, which can be what you want, here choosing h.

%28%282%2F%28x%2Bh%29%5E2%29-%282%2Fx%5E2%29%29%2Fh, the difference quotient, how to start.
From here you have much algebra steps. ultimately you want to take the value of h to zero to decide what is the expression for the derivative.