Question

1. If (27x3 -343y3) / (3x - 7y) = Ax2 + By2 + 7Cyx,
then the value of (4A-B+5C) is:​

Answer 1

Answer:

जैसा कि हम जानते हैं, x3 – y3 = (x – y) (x2 + y2 + xy)

⇒ (27x3 – 343y3) ÷ (3x – 7y) = Ax2 + By2 + 7Cxy

⇒ [(3x)3 – (7y)3] ÷ [(3x – 7y)] = Ax2 + By2 + 7Cxy

⇒ [(3x – 7y) (9x2 + 49y2 + 21xy)] ÷ [(3x – 7y)] = Ax2 + By2 + 7Cxy

⇒ 9x2 + 49y2 + 21xy = Ax2 + By2 + 7Cxy

तुलना करने पर

⇒ A = 9, B = 49 और C = 3

⇒ 4A – B + 5 × 3

⇒ 4 × 9 – 49 + 5 × 3 = 2