Mathematics
Answer
Given,
⇒ x6 - 1
⇒ (x3)2 - (1)2
By using the identity,
(a2 - b2) = (a + b)(a - b)
⇒ (x3 - 1)(x3 + 1)
⇒ [x3 - (1)3][x3 + (1)3]
⇒ (x - 1)[(x)2 + x × 1 + 12] [(x + 1)(x)2 - x × 1 + 12]
⇒ (x - 1)(x2 + x + 1)(x + 1)(x2 - x + 1)
⇒ (x - 1)(x + 1)(x2 + x + 1)(x2 - x + 1).
Hence, x6 - 1 = (x - 1)(x + 1)(x2 + x + 1)(x2 - x + 1).