What is the reciprocal of -1/2

The reciprocal of −1/2 is −2. A nonzero number and its reciprocal multiply to one. Reversing the numerator and denominator of a fraction preserves the negative sign.

Meaning and context

Write −1/2 as a fraction with numerator −1 and denominator 2. Reversing gives 2/(−1), which equals −2. The sign does not become positive simply because the fraction is inverted.

Examples and usage

Check the result: (−1/2) × (−2) = 1. Two negative factors produce a positive product. By contrast, adding the two numbers would not give the reciprocal test, because reciprocals concern multiplication.

What to check

Zero has no reciprocal because division by zero is undefined. Also distinguish a reciprocal from an opposite: the opposite of −1/2 is +1/2, while its reciprocal is −2. The operation named in the question determines which answer is appropriate.

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