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Does the rational number 0 have a multiplicative inverse?

AYes, it is 0 itself
BYes, it is 1
CNo, because 1/0 is undefined
DYes, but only when multiplied by another zero
Answer & Solution
Correct answer: C. No, because 1/0 is undefined
For any non-zero rational a, the multiplicative inverse is 1/a. But 1/0 is not defined (division by zero is forbidden), so 0 has no multiplicative inverse. **Equivalently:** there is no rational number x such that 0 × x = 1.
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