Question

Find the cube root by prime factorisation,

(i) 1728

(ii) 3375

(iii) 10648

Answer 1

(i) 1728 = 2 × 2 × 2 × 6 × 6 × 6

= 12 × 12 × 12

3(\sqrt{1728}) = 12

(ii) 3375 = 5 × 5 × 5 × 3 × 3 × 3

= 15 × 15 × 15

(iii) 10648 = 2 × 2 × 2 × 11 × 11 × 11

= 2 × 11 × 2 × 11 × 2 × 11

= 22 × 22 × 22

10648 = 223