Step-by-step explanation:
the inverse function simply calculate the original x it of a given y. so, we need to transform the original function to calculate x instead of y.
and then, at the end to make it a formally correct function definition, we rename x to y and y to x.
y = x + 3
x = y - 3
=> to make it a formally correct function definition
y = x - 3 = h(x)
