The LCM and HCF of polynomials is (x2 – y2) and (x2 + xy + y2). If one of the polynomial is (x + y) then, what will be the other polynomial?
The LCM and HCF of polynomials is (x2 – y2) and (x2 + xy + y2). If one of the polynomial is (x + y) then, what will be the other polynomial? Correct Answer x<sup>3</sup> – y<sup>3</sup>
Given:
The LCM and HCF of polynomials is (x2 – y2) and (x2 + xy + y2)
One of the polynomial is (x + y)
Formula used:
Product of polynomial = Product of HCF and LCM of polynomials
p(x) × q(x) = LCM of (p(x) and q(x)) × HCF of (p(x) and q(x))
Identity: a2 – b2 = (a + b) × (a - b)
Identity: a3 – b3 = (a – b) × (a2 + ab + b2)
Calculation:
Let the other polynomial is q (x, y)
∴ q(x, y) = {LCM of (p(x, y) and q (x, y)) × HCF of (p(x, y) and q(x, y))}/p(x, y)
⇒ q(x, y) = {(x2 – y2) × (x2 + xy + y2)}/(x + y)
Now, we know the identify a2 – b2 = (a + b) × (a – b)
∴ q(x, y) = {(x + y) × (x – y) × (x2 + xy + y2)}/(x + y)
⇒ q(x, y) = (x – y) × (x2 + xy + y2) = x3 – y3
Hence, option (1) is correct