The function is one to one Find the inverse A Fx67x4 B Fx9x8

Solution

A) f(x) = 6/(7x -4)

f^-1f(x) = 6/(7f^-1(x) -4)

  (7f^-1(x) -4) = 6/x

f^-1(x) = (6/x + 4)/7 = (4x + 6)/7x

B) f(x) = (9x-8)/(5x-4)

f^-1f(x) = (9f^-1(x)-8)/(5f^-1(x)-4)

x(5f^-1(x)-4) = 9f^-1(x)-8

(5x - 9)f^-1(x) = 4x - 8

  f^-1(x) = (4x - 8)/(5x - 9)