Stuck on Math Problem: Finding the Derivative

[KF33]

Homework Statement

I have been working on the problem below and I am stuck. I am stuck primarily because of the part where is says x=0. If x-0, it should cancel everything out. The derivative of 0 is 0 so will cancel everything out I think, so I am not sure if that is the reasoning and the proof behind it.

Homework Equations

The Attempt at a Solution

I thought I should start this way, but I am not 100% sure.[/B]

 

[SammyS]

Homework Statement

I have been working on the problem below and I am stuck. I am stuck primarily because of the part where is says x=0. If x-0, it should cancel everything out. The derivative of 0 is 0 so will cancel everything out I think, so I am not sure if that is the reasoning and the proof behind it.

Homework Equations

The Attempt at a Solution

I thought I should start this way, but I am not 100% sure.[/B]
View attachment 102534

It's a good idea to have the problem statement visible in the OP.

 

[James R]

L'Hopital's rule?

 

[micromass]

L'Hopital's rule?

Not necessary with the hint in the OP, the definition of a derivative is enough.