When the product of two numbers is one, they are called reciprocals or multiplicative inverses of each other. For example, and are reciprocals because . This is the motivation for the following property of fractions.
Inverse Property for Fraction Multiplicationwhere a and b are nonzero. The fraction is called the multiplicative inverse of (or reciprocal) and vice versa.
Notice that a reciprocal (multiplicative inverse) can be formed from any common fraction by exchanging the positions of the numerator and denominator. The reciprocal of is , of is , and is . The reciprocal (multiplicative inverse) for a mixed number is found by first changing the mixed number to an improper fraction. For example, so the reciprocal of is .
Find the reciprocal (multiplicative inverse) for each of the following.


7 

0 



Important Note. The reciprocal of zero is undefined.
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