I know the answer, but I just need a little help getting it.
It's all in here:
http://i44.tinypic.com/o7r6yv.jpg
Thanks so much!
I know the answer, but I just need a little help getting it.
It's all in here:
http://i44.tinypic.com/o7r6yv.jpg
Thanks so much!
Differentiate $\displaystyle \frac{8-3t^2}{(8+t^2)^3} = (8-3t^2)(8+t^2)^{-3}$
The derivative is:
$\displaystyle -6t (8+t^2)^{-3} + (8-3t^2)(-3)(2t)(8+t^2)^{-4}$
Put in common denominator:
$\displaystyle \frac{-6t(8+t^2)}{(8+t^2)^4} + \frac{-6t(8-3t^2)}{(8+t^2)^4}= $
$\displaystyle \frac{-48t-6t^3-48t+18t^3}{(8+t^2)^4} =$
$\displaystyle \frac{-96t+12t^3}{(8+t^2)^4}=$
$\displaystyle \frac{-12t(8-t^2)}{(8+t^2)^4} $
Good luck!