Question

Given the function f(x) = 4(x+3) − 5, solve for the inverse function when x = 3.

Answer 1

`f(x)=4(x+3)-5 \\ f(x)=4x+12-5 \\ f(x)=4x+7 \\ \\ \hbox{solve for x:} \\ y=4x+7 \\ y-7=4x \\ x=(y-7)/(4) \\ \\ \hbox{swap x and y:} \\ y=(x-7)/(4) \\ \\ f^(-1)(x)=(x-7)/(4) \\ f^(-1)(3)=(3-7)/(4)=(-4)/(4)=-1 \\ \boxed{f^(-1)(3)=-1}`