Posted by Hannah on Tuesday, February 22, 2011 at 9:06pm.
use the quotient rule to find derivative.
y= 3x^2+8 / x^2+3
(x^2+3)(6x)  (3x^2+8)(2x) all over (x^2+3)^2
The answer is 2x/(x^2+3)^2
The only problem is I am not sure how they simplified this to get the answer.

math  Reiny, Tuesday, February 22, 2011 at 9:14pm
Just expand and simplify your numerator.
[(x^2+3)(6x)  (3x^2+8)(2x)] / (x^2+3)^2
= (6x^3 + 18x  6x^3  16x)/(x^2+3)^2
= 2x/(x^2+3)^2