Question

Find the square root of the following number by the prime factorisation method.
$1521$

Answer 1

The factors of $1521$ is,

$1521=3\times 3\times 13\times 13$

Take square root both sides,

$\sqrt{1521}=\sqrt{3\times 3\times 13\times 13}$

$=\sqrt{3^2\times {13}^2}$

$=\sqrt{{\left(3\times 13\right)}^2}$

$=39$

Therefore, the square root of 1521 is 39.