# Thread: derivative QUESTION check!

1. ## derivative QUESTION check!

differentiate :

$
\frac{x^2tanx}{x^2+1}
$

$
=\frac{(x^2+1)(2xtanx + x^2sec^2x)-(x^2tanx)(2x)}{(x^2+1)^2}
$

correct?

2. Originally Posted by jvignacio
differentiate :

$
\frac{x^2tanx}{x^2+1}
$

$
=\frac{(x^2+1)(2xtanx + x^2sec^2x)-(x^2tanx)(2x)}{(x^2+1)^2}
$

correct?
Correct!

--Chris

3. Originally Posted by Chris L T521
Correct!

--Chris
Yay ! thank u

4. Correct indeed, but I'd want to play with it and tidy it up and simplify it down as much as possible before letting it go.

5. Originally Posted by Matt Westwood
Correct indeed, but I'd want to play with it and tidy it up and simplify it down as much as possible before letting it go.

yeah i have abit of problem with the algrebra n simplifying

6. Not good news. Essential to get good at algebra. It's like needing to be good at grammar and spelling if you want to be a writer. Give yourself all the practice you can get.

7. $f(x)=\frac{x^{2}\tan x}{x^{2}+1}=\frac{x^{2}+1-1}{x^{2}+1}\cdot \tan x=\tan x-\frac{\tan x}{x^{2}+1}.$