for non-negative real numbers, the square root refers to the real number that is equal to the result of multiplying by itself. it is expressed as ± (√x) and is read as x or the square root of x under the positive and negative root signs. the non-negative square roots are called arithmetic square roots. the square root of a positive integer is usually an irrational number. it can be uniquely defined by the following formula: in fractional exponents, we have: according to the definition, it can be seen that the square root operation satisfies the distributive law for multiplication, that is: note that if n is a non-negative real number and time, because it must be a positive number, but there are two positive and negative solutions . should be equal to ±; that is (see absolute value).