Question 61898
The given function is: 


f(x) = 3x - 7 


To find f<sup>-1</sup>(x) 


Let y = f(x) = 3x - 7 


therefore,


y = 3x - 7


Now solve for "x" from this: 


y + 7 = 3x                   [Adding 7 on both sides, we get]


{{{(y + 7)/3}}} = x             [Divide by 3] 


So now, we have 


x = {{{(y + 7)/3}}}


Thus, f<sup>-1</sup>(y)= {{{(y + 7)/3}}}


Thus, replacing x by y, we get: 



f<sup>-1</sup>(x)= {{{(x + 7)/3}}}


Hence, the solution.