√21*√3 = ?

2016-07-17 9:14 pm

回答 (7)

2016-07-17 9:17 pm

✔ 最佳答案

√21 × √3

= √(3 × 7) × √3

= √3 × √7 × √3

= √3 × √3 × √7

= (√3)² × √7

= 3√7

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2016-07-18 7:23 am

√63 =√9 x √7 = 3√7

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2016-07-18 12:08 am

sqrt(21) * sqrt(3) = sqrt(3 * 7) * sqrt(3) = 3 sqrt(7).

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2016-07-17 9:23 pm

√21 √3 = √63 = 3 √7

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2016-07-17 9:22 pm

√3 * √21 =
√3 * √3 * √7 =
3√7

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2016-07-17 9:19 pm

√21*√3= √63

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2016-07-17 9:15 pm

sqrt(21 * 3)

Which can be simplified since 21*3 contains a factor of 9 = 3^2. And what is the square root of 3^2?

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