Question #d780a

1 Answer
Jul 5, 2017

#(g circ f)^(- 1) = - frac(1)(28) (x + 11)#

Explanation:

We have: #f(x) = 4 x + 3# and #g(x) = - 7 x + 10#

First, let's evaluate #g circ f#:

#Rightarrow g circ f = g (f(x))#

#Rightarrow g circ f = g (4 x + 3)#

#Rightarrow g circ f = - 7 (4 x + 3) + 10#

#Rightarrow g circ f = - 28 x - 21 + 10#

#Rightarrow g circ f = - 28 x - 11#

Let's suppose #y = g circ f#.

We must now find the inverse of #y#:

#Rightarrow y = - 28 x - 11#

Interchanging variables:

#Rightarrow x = - 28 y - 11#

Let's solve for #y#:

#Rightarrow x + 11 = - 28 y#

#Rightarrow y = - frac(1)(28) (x + 11)#

#therefore (g circ f)^(- 1) = - frac(1)(28) (x + 11)#