+0

# Composite function rule

0
365
2
+70

3/4(2x + 7)9

-27/2(2x+7)10

My denominator doesn't equal to 2 when I try to work it out is the answer wrong or me? Help :'(

Thank you

Ashreeta  Aug 15, 2017
edited by Ashreeta  Aug 15, 2017
#1
0

differentiate (2x+7) (chain rule) than you get denominator equal 2

Guest Aug 15, 2017
#2
+7023
0

$$\dfrac{d}{dx}\dfrac{3}{4(2x+7)^9}\\ =\dfrac{3}{4}\dfrac{d}{dx}\dfrac{1}{(2x+7)^9}\\ =\dfrac{3}{4}\left(\dfrac{d}{dx}(2x+7)\right)\cdot\dfrac{-9}{(2x+7)^{10}}\\ =\dfrac{3}{4}\cdot 2\cdot -9\cdot \dfrac{1}{(2x+7)^{10}}\\ =\dfrac{-27}{2(2x+7)^{10}}$$

So there u go, with a denominator equals 2.

MaxWong  Aug 15, 2017