Question

Suppose that
f(4) = 4 f'(4) = -2
g(4) = 5 g'(4) = -3
Find the derivative of the quotient function
f(x)/g(x) at x = 4
How do I approach this problem?

Answer 1

know chain rule and quotient rule ?

Answer 2

yeah

Answer 3

apply quotient rule to get d/dx f/g
what u get ?

Answer 4

[f(x)/g(x)]' = g(x)f'(x) - f(x)g'(x) / [g(x)]^2

Answer 5

I just input the x and simplify?..

Answer 6

yes!

Answer 7

you have all the values given...

Answer 8

so
g(4)f'(4) - f(4)g'(4) / (g(4))^2
5(-2) - 4(-3) / 25
-10 + 12 / 25
2/25

Answer 9

good! :)