Question

Which of the following integers are cubes of negative integers ?

(i) -64

(ii) -1056

(iii) -2197

Answer 1

(i) -64

64 = 2 × 2 × 2 × 2 × 2 × 2

= 23 × 23

= 43

∴ 64 is a perfect cube of negative integer – 4.

(ii) -1056

1056 = 2 × 2 × 2 × 2 × 2 × 3 × 11

1056 is not a perfect cube.

∴ -1056 is not a cube of negative integer.

(iii) -2197

2197 = 13 × 13 × 13

= 133

∴ 2197 is a perfect cube of negative integer – 13.