The reciprocal or multiplicative inverse of a number is the number which, when multiplied by , gives .
So, the product of a number and its reciprocal is . (This is sometimes called the property of reciprocals .)
so the reciprocal of is (and the reciprocal of is .)
so and are reciprocals.
Note that zero has no reciprocal .
Reciprocals are used to solve simple linear equations, for instance:
To solve, multiply both sides by the reciprocal of .