What numbers can be used in a square root?

1 Answer
Apr 9, 2018

Any numbers can be used in a square root. The square root symbol (sqrt) is called a radical and the number whose square root is being considered is called a radicand. All nonnegative real numbers have two possible square roots: a positive and a negative one. For example, sqrt(5) can be equal to 5 of -5 as the product of two negative numbers is always positive. When a negative number is the radicand, the answer will be in terms of i, which is an imaginary number that is sqrt(-1). For example, sqrt(-5) = sqrt(-1)*sqrt(5) = isqrt(5).