Question

Find the cube root of 13824 using the prime factorisation method.

Answer 1

Factorising 13824 using the prime factorisation method,

$\begin{array}{cc}2& 13824\\ 2& 6912\\ 2& 3456\\ 2& 1728\\ 2& 864\\ 2& 432\\ 2& 216\\ 2& 108\\ 2& 54\\ 3& 27\\ 3& 9\\ 3& 3\\ & 1\\ & \end{array}$

$\sqrt[3]{313824}=\sqrt[3]{32\times 2\times 2\times 2\times 2\times 2\times 2\times 2\times 2\times 3\times 3\times 3}=2\times 2\times 2\times 3=24$