If n is an integer, then (n3 – n) is always divisible

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If n is an integer, then (n³ – n) is always divisible by :

1. 4
2. 5
3. 6
4. 7

Correct Option: C

n³ – n = n (n + 1) (n – 1)
n = 1, n³ – n = 0
n = 2, n³ – n = 2 × 3 = 6
n = 3, n³ – n = 3 × 4 × 2 = 24
n = 4, n³ – n = 4 × 5 × 3 = 60
⇒ 60 ÷ 6 = 10
Hence , required answer is 6.