Calculus - Derivative of a Function

[bobraymund]

Homework Statement

Find the derivative of the function.

Homework Equations

The Attempt at a Solution

I have tried this out and came up with an answer that I'm not too confident with, I got:

I would show my work on here, but don't know how to exactly, so my bad. Thanks in advance,
Bob

 

[pbandjay]

That's what I got, and my calculator agrees.

Hint: e^u * e^-u = 1.

 

[womata]

That's what I get too.

 

[HallsofIvy]

you can also note that x= tanh(u) and the derivative of tanh(u) is sech²(u).

 

[bobraymund]

Wow, thanks a lot for the prompt responses. Normally I'd post something like this on Yahoo Answers and not get an answer for a few days.

Again, thanks a bunch.

-Bob