What is the algorithm for the inverse of f (x)?

Answer:
What is an inverse?
Recall that a number multiplied by its inverse equals 1. From basic arithmetic we know that:
The inverse of a number A is 1/A since A * 1/A = 1 (e.g. the inverse of 5 is 1/5)
All real numbers other than 0 have an inverse
Multiplying a number by the inverse of A is equivalent to dividing by A (e.g. 10/5 is the same as 10* 1/5)
What is a modular inverse?
In modular arithmetic we do not have a division operation. However, we do have modular inverses.
The modular inverse of A (mod C) is A^-1
(A * A^-1) ≡ 1 (mod C) or equivalently (A * A^-1) mod C = 1
Only the numbers coprime to C (numbers that share no prime factors with C) have a modular inverse (mod C)
Step-by-step explanation:
Please check image.