f(x)= 1/2 (3-3x)
First, write as a linear equation: (replace f(x) by y)
y= 1/2 (3-3x)
Swap x and y variables:
x = 1/2 (3-3y)
Solve for y:
x = 1/2(3)+1/2(-3y)
x= 3/2 -3/2y
x-3/2 = -3/2y
(x-3/2) / -3/2 = y
-2/3x+1=y
Write in inverse notation
f-1(x) = -2/3x+1
