If (5√5 x3– 81√3 y3) ÷ (√5 x – 3√3 y) = (Ax2+ By2+ Cxy) then the value of (6A + B – √15 C) is:
Show answer & explanation
Correct answer: A
Explanation
Correct answer is option 1 i.e. 12
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Concept |
Understanding |
Application |
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A3 – B3 = (A – B) (A2 + B2 + AB) |
(5√5x3 – 81√3y3) ÷ (√5x – 3√3y) = Ax2 + By2 + Cxy
Expand and compare the coefficients |
[(√5x - 3√3y) (5x2 + 27y2 + 3√15xy)]/(√5x-3√3y) ⇒ (5x2 + 27y2 + 3√15xy) = (Ax2 + By2 + Cxy) ⇒ A = 5, B = 27, C = 3√15 Hence, (6A + B - √15C) = 6 × 5 + 27 – √15 × 3√15 = 1 |