square roots

What is a square root?

A square root of a number x is a number y such that y^2 = x. For example, 4 is a square root of 16 because 4^2 = 16. Also, -4 is a square root of 16 because (-4)^2 = 16.

What symbol is used to denote the principal (non-negative) square root of a number?

The radical symbol, \sqrt{}. For example, the principal square root of 25 is written as \sqrt{25}.

What is a perfect square?

A perfect square is an integer that can be expressed as the square of an integer. For example, 1, 4, 9, 16, 25 are perfect squares because they are 1^2, 2^2, 3^2, 4^2, 5^2 respectively.

What is the principal square root of a number?

The principal square root of a non-negative number x (denoted as \sqrt{x}) is the unique non-negative number y such that y^2 = x. For example, the principal square root of 16 is 4, not -4.