The inverse of 7x ix x/7
The composition of the function and its inverse must be zero. So the composition of 7x with x/7 is:
[tex](F( F^{-1}x)) \\ \\ =F( \frac{x}{7}) \\ \\ = 7(\frac{x}{7}) \\ \\ = x [/tex]
Thus, 7x and x/7 are inverse of each other.
So the answer to this question is option B