What is square root of 21?

The square root of 21 is an irrational number, meaning it cannot be expressed as a fraction or a terminating or repeating decimal. It is approximately equal to 4.58257569 when rounded to eight decimal places.

The square root of 21 can also be calculated using the prime factorization method. It can be written as the square root of (3 * 7). Taking the square root of each prime factor individually, the square root of 21 can be simplified to √3 * √7. Both √3 and √7 are irrational numbers on their own.

The square root of 21 can be used in various mathematical calculations, such as solving quadratic equations, evaluating geometric problems, and understanding the relationship between sides and diagonals in a square or rectangle with an area of 21.