What is the instantaneous rate of change of f(x)=1/(x^2+2x+3 )f(x)=1x2+2x+3 at x=0 x=0?

1 Answer
Mar 10, 2016

-2/9 29

Explanation:

This is just the value of f'(0)

f(x) = 1/(x^2+2x+3) = (x^2+2x+3)^-1 f(x)=1x2+2x+3=(x2+2x+3)1

using the color(blue) " chain rule " chain rule

d/dx[f(g(x))] = f'(g(x)). g'(x)

rArr f'(x) = - (x^2+2x+3)^-2 d/dx(x^2+2x+3)

= -(2x+2)/(x^2+2x+3)^2

and f'(0) = - 2/(3^2) = -2/9