Exercise · ZW-FUNDAMENTAL-THEOREM-OF-ARITHMETIC-009 · ★★☆ Intermediate

How many positive divisors does \(60 = 2^2 \cdot 3 \cdot 5\) have?

Choose one option.

Show answer
  • A. \(12\)

Explanation

The count is \((2+1)(1+1)(1+1) = 12\). The option 6 does not follow the multiplicative formula, and the one with 8 ignores the factor from the prime 2.

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Review the concept: Fundamental theorem of arithmetic

Every integer greater than 1 can be written uniquely as a product of primes, up to the order of the factors. It is the foundation of most of elementary number theory.

\[n = p_1^{a_1} p_2^{a_2} \cdots p_k^{a_k}\]

More practice problems: fundamental theorem of arithmetic

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