y=2x+13x−2
First off note that this isn't defined at x=2/3 but other than that it is one to one.
(3x−2)y=2x+1
3xy−2y=2x+1
x(3y−2)=1+2y
x=1+2y3y−2
now just replace x by f-1(x) and y by x to obtain
f−1(x)=2x+13x−2 ∀x≠23