Question

Given the function f(x) = 6(x+2) − 3, solve for the inverse function when x = 21

Answer 1

Hello,

f(x)=6(x+2)-3=6x+12-3=6x-9

y=6x-9==>x=6y-9==>6y=x+9==>y=(x+9)/6
if x=21 then y=(21+9)/6=30/6=5

f^(-1)(21)=5