Square root of 40

√40 ≈ 6.3246

√40 is an irrational number, so its decimals never end or repeat. It sits between 6 and 7 because 6² = 36 and 7² = 49.

√40 rounded

Simplest radical form

40 = 4 × 10 and √4 = 2, so √40 = 2√10.

Check the answer

6.3246 × 6.3246 ≈ 40.0006, which is very close to 40.

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Square roots near 40

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