Find the smallest positive integer such that is a perfect square.
Answer and explanation
Correct answer: B. 2
- Step 1: Factorise: .
- Step 2: A perfect square needs every exponent even, so multiply by the primes with odd exponent: .
Answer
2.
Why not the others: 18: it uses itself. 4: an extra factor is included. 5: it adds the prime factors.
Practise more Properties of Integers.
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