Question

РЕШИТЕ:(x+2y)^2+2x(-7x-2y)
y(3y+4x)-(x+2y)^2
24ab-6(-2a-b)^2

Answer 1

(x+2y)²+2x(-7x-2y) = х²+4ху+4у²-14х²-4ху = -13х²+4у²
y(3y+4x)-(x+2y)² = 3у²+4ху-(х²+4ху+4у²) = 3у²+4ху-х²-4ху-4у² = -у²-х²
24ab-6(-2a-b)² = 6(4ab-(2a-+b)²) = 6(4ab-(4a²+b²)) = 6(4ab-4a²-4ab-b²) = 6(-4a²-b²) = 6*(-(4a²+b²)) = -(6(4a²+b²)) = -6(4a²+b²)