Another derivative confirmation.

[Sakha]

Homework Statement

Find the derivative of:
f(x)= ((x+xsinx)/(1+2tan²x))³

The Attempt at a Solution

I solved it and got :
f'(x)= (3(1+2tan²x)³(x+xsinx)²(sinx+xcosx+1)-12(x+xsinx)³(2tan²x+1)²(tanxsec²x))/(1+2tan²x)⁶

Can anyone confirm if this is alright?
Also, anyone knows a webpage that has an online calculator that would confirm this kind of math problems?
Thanks.

 

[radou]

Here's what I got in Mathematica, I'm too lazy to do the algebra to compare. See attachment. Btw, Sec(x) = 1 / Cos(x).

 

[Sakha]

I'm more than lazy to do this algebra. There has to be a way of comparing answers in WolframAlpha's Mathematica.

 

[Saladsamurai]

You also use Wolframalpha.com if you don't have Mathematica. See here.

 

[Sakha]

What I meant is that there has to be some feature in WolframAlpha to compare functions and see if they are algebraically equal. Like comparing Mathematica's answer to my derivative, to my derivative.

 

[Saladsamurai]

Perhaps plugging in a few specific values into both and seeing what happens would suffice? Or don't be lazy The algebra doen't look that bad.