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The square root of -21 is: 4.582576 i

Q: What is the square root of 21?

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Yes, as is the positive square root.

First note that 84=4x21 and 4 is a perfect square. So square root of (84)=square root (4x21)=Square root (4) Square root (21)= 2 multiplied by the square root of 21. You can also write this using rational exponents, but this is not in radical form. It is an equivalent expression, however. 2 x (21)1/2

21

It is: 2 times the square root of 21 and it's an irrational number

plus or minus 21

Related questions

The square root of 21 is 4.58257569495584.

4.6 is a better approximation to the square root of 21.

21

Root 64 is 8, if by root you mean the square root. Then the problem become -square root 84(6+8) which is the - square root of 84(14) But square root of 84 is 2(square root of 21) so the final answer comes from -2(square root 21)x14 which is -28square root (21)

21The square root of 441 is 21

Your answer is: 17.7482393

The square root and square functions are inverse of one another EXCEPT that square root is not really a function: it is a 1-to-many mapping. So sqrt(square(21)) = sqrt(441) = Â±21

(√(a))²=a The square root and the square cancel to leave just 49/21■

Yes, as is the positive square root.

21 times the square root of 5.

First note that 84=4x21 and 4 is a perfect square. So square root of (84)=square root (4x21)=Square root (4) Square root (21)= 2 multiplied by the square root of 21. You can also write this using rational exponents, but this is not in radical form. It is an equivalent expression, however. 2 x (21)1/2

There is no exact value for the square root of 21. √21 = 4.5825757 (7dp)