Question

What is a reciprocal of a number?

Answer 1

The reciprocal of a number, `a`, is a number, `b` such that
`a xx b = 1`

For Real numbers, other than 0, the reciprocal of `a` is `1/a`.

(The number `0` does not have a reciprocal because `0xxb=1` has no solution. `0xxn=0` for all real and complex `n`.)