The square root of a positive number results in a positive number. For example, the square root of 25 is 5. * * * * * Not true! There are two real square roots for every positive number: one positive and one negative. -5 is as much a square root of 25 as +5 is. However, the positive root is the principal root and so is often presented as the only root.
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It is: 25
The positive square root is.
You cannot in real numbers because the square of any number, negative or positive, is positive. However, -25 does have a square root in complex numbers: it is + or - 5i where i is the imaginary square root of -1.
The square root of a positive number results in a positive number. For example, the square root of 25 is 5. * * * * * Not true! There are two real square roots for every positive number: one positive and one negative. -5 is as much a square root of 25 as +5 is. However, the positive root is the principal root and so is often presented as the only root.
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The square root of 25 has two solutions: SQRT(25) = + 5 and -5The square root of a number, by definition, should be positive. Hence, the square root of 25 is 5. The other square root is -5. However, strictly speaking, -5 is not the square root of 25, since it is not a positive number.* * * * *The exclusion of the negative square root is plain nonsense.
It is: 25
The positive square root is.
You cannot in real numbers because the square of any number, negative or positive, is positive. However, -25 does have a square root in complex numbers: it is + or - 5i where i is the imaginary square root of -1.
The principal root of a number is the positive real square root of the number - if it exists. Since -25 is negative, it does not have a real square root. Its square roots are the imaginary numbers +/-5i where i is the [imaginary] square root of -1. i is neither positive nor negative and so neither +5i nor -5i is a principal root.
Restricting the discussion to real numbers for now. In this case, the square root is only defined for non-negative numbers; the principal square root of a positive number is the POSITIVE square root. For example, both +5 and -5 are square roots of 25, since both - when squared - give you 25. But the positive square root (+5) is called the principal square root, and if you write the square root symbol, that's the number usually meant.
That refers to the positive root, at least if you take the root of a positive number. For example, 25 has two square roots - two numbers which, when squared, give 25. The positive one (+5) is called the principal square root (or 2nd. root).
Sometimes the square root of a positive number can be irrational, as in the square root of 2 (which is a non-perfect square number), but sometimes it is a rational number, as in the square root of 25 (which is a perfect square number).
Because the square root of -25 would be that number that, squared, would equal -25. No number, positive or negative, can result in a negative square. Since -25 is a negative number, no number, positive or negative, can be squared to equal -25.
A number will have both a positive and negative square root 5 x 5 = 25 and -5 x -5 = 25.