Derivatives

Apr 2010
25
0
What is the derivative of f(x) = -x^2 + 4x - 10 / (x^2 - 3x - 4)^2

I calculated it to be f'(x) = (-2x + 4)(x^2 - 3x - 4)^2 - (-x^2 + 4x - 10)(2)(x^2 - 3x - 4)(2x-3) / (x^2 - 3x - 4)^4

apparently this is wrong according to graphing technology.
 

skeeter

MHF Helper
Jun 2008
16,216
6,764
North Texas
What is the derivative of f(x) = -x^2 + 4x - 10 / (x^2 - 3x - 4)^2

I calculated it to be f'(x) = (-2x + 4)(x^2 - 3x - 4)^2 - (-x^2 + 4x - 10)(2)(x^2 - 3x - 4)(2x-3) / (x^2 - 3x - 4)^4

apparently this is wrong according to graphing technology.
it's not wrong, just needs an algebra clean-up ... your syntax may be where the problem lies.