Which of the following is NOT equal to the square of an integer:

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Gmat_mission wrote:
Sun Aug 15, 2021 3:29 pm
Which of the following is NOT equal to the square of an integer:

A. \(\sqrt{\sqrt{1}}\)

B. \(\sqrt4\)

C. \(\dfrac{18}2\)

D. \(41 - 25\)

E. \(36\)

Answer: B
Although every positive number has two square roots, the square root notation (√) tells us to take only the positive root
So, for example, 9 has two square roots (3 and-3), since 3² = 9 and (-3)² = 9
However, the square root notation tells us to take the positive root, which means √9 = 3

Likewise, √1 = 1 (only)

Cheers,
Brent
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