Question

Derive the inverse of the function, f-1 of f(x) = 7x+2

Answer 1

Replace f(x) with y
switch x and y
solve for y
replace y with f^-1

so

y=7x+2
x=7y+2
x-2=7y
(x-2)/7=y
f^-1=(x-2)/7

inverse is
$f^{-1}= \frac{x-2}{7}$