We have to remember that in one-to-one functions each element of the domain maps to a different element in the range.
When we have a bijection we have that each element in the set A, for example, corresponds to exactly one element of B, and vice versa.
When we have a bijection, we also have an inverse function.
Then, we have that:
To find the inverse, we have to interchange the variables:
Now, we have:
And we need to solve for y:
1. Add 13 to both sides of the equation:
2. Divide both sides by -2:
Then, we have that:
We can check this if we make a composition between the two functions (then we will get x as a result).
Then, we have that the result for this composition is equal to x. Thus:
We also have that:
We have that h(4) = 3, then h^(-1)(3) = 4 or
In summary, we have: