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The product of a non-zero rational number and an irrational number is always:
ARational
BIrrational
CEither rational or irrational
DZero
Answer & Solution
Correct answer: B. Irrational
If r is a non-zero rational and x is irrational, then r × x must be irrational. If it were rational, then x = (r × x) / r would be rational (a ratio of two rationals), contradicting x being irrational.
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