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  9. Q136

TNPSC Group-I 2021 · Question 136 of 148

Find the LCM of (x^4 - 1) and (x^2 - 2x + 1).

Aptitude - Algebra

  1. A(x^2 + 1)(x + 1)
  2. B(x + 1)(x - 1)
  3. C(x^2 + 1)(x + 1)^2
  4. D(x^2 + 1)(x + 1)(x - 1)^2Correct

Answer: D. (x^2 + 1)(x + 1)(x - 1)^2

Explanation

x^4 - 1 = (x-1)(x+1)(x^2+1); x^2 - 2x + 1 = (x-1)^2. LCM = (x-1)^2 (x+1)(x^2+1).

Source: TNPSC Group-I Prelims (held 3 Jan 2021) - official paper via examrace.com

← Q135View full paper (148 questions)Q137 →

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