hmmm,
a function can be determined by the vertical line test
if you can draw a vertical line that passes through the graph twice, it is not a function
the inverse is the graph reflected across the line y=x
we can determine the answer to this question graphically
take y=x^2 for example
this is a function
reflected across the line y=x, and it is not a function
it fails the vertical line test
but, we can also take y=3x and reflect it and it is still a function
so the answer is sometimes