diketahui f(x)=5x + 7 tentukan fungsi komposisi (fof-1) (x)dan (f-1 of) (x)

[tex]f(x) = 5x + 7 \\ x = \frac{y-7}{5} \\ f^{-1}(x) = \frac{x - 7}{5} \\ (f o f^{-1})(x) = f(\frac{x-7}{5} ) \\ = 5(\frac{x-7}{5}) + 7 \\ = x \\ \\ (f^{-1} o f)(x) = f^{-1}(5x + 7) \\ = \frac{(5x+7)-7}{5} \\ = x[/tex]