CDS 2026 · PYQ · Algebra / LCM-HCF of Polynomials · medium
The LCM and HCF of two polynomials p(x) and q(x) are (x + a)(x³ – a³) and (x² – ax + a²), respectively. If p(x) = x⁴ + a²x² + a⁴, then what is q(x) equal to?
Answer
The correct answer is C: x² – a². Using the relation p(x) × q(x) = LCM × HCF. LCM = (x+a)(x³ – a³) = (x+a)(x–a)(x²+ax+a²) = (x²–a²)(x²+ax+a²).