step 1: replace f(x) with y ⇒ y=[tex] \frac{19}{ x^{3} } [/tex]
step 2: switch the x and y ⇒ x=[tex] \frac{19}{ y^{3} } [/tex]
step 3: solve for y using algebra ⇒ [tex] xy^{3} =19 [/tex] ⇒ [tex] y^{3}= \frac{19}{x} [/tex] ⇒ [tex]y= \sqrt[3]{ \frac{19}{x} } [/tex]
step 4: switch y to [tex]f ^{-1}(x) [/tex] and this known as "the inverse of f(x)