If the square of a nonnegative X is equal to A, then this nonnegative X is called the arithmetic square root of A, and the arithmetic square root of A is recorded as the "root number A", and A is called the radix. The operation of finding the square root of a non-negative number is called square root.
Conclusion: The greater the number of roots, the greater the corresponding arithmetic square root (true for all positive numbers). If a positive number has a square root, then there must be two, and it is reciprocal.
Square root is also called quadratic square root, which is expressed as √ ~ where the non-negative square root is called arithmetic square root. Positive numbers have two real square roots in opposite directions; 0 has only one square root, which is 0 itself; The square root of a pure imaginary number with two yokes.