Respuesta :

altavistard
Let's make up a linear function:  y = mx + b.

Find its inverse:

1) interchange x and y:   x = my + b                      x-b
2) solve this result for y:        my = x - b, or   y = ----------
                                                                                m
                             -1
3) replace y by  f      (x)

So long as m is not zero, this function is defined for all x.