Question

4a^2-4ab+b^2:4a^2-b^2 при а =1:11 b=-9:11​

Answer 1

4а²-4ав+в²/4а²-в²=(2а-в)²/(2а-в)(2а+в)=2а-в/2а+в

подставляем значения

2/11-9/11  / 2/11+9/11=-7/11

Answer 2

$\frac{ {(2x - y)}^{2} }{(2x - y)(2x + y)} = \frac{2x - y}{2x + y}$
$\frac{ \frac{2}{11} + \frac{9}{11} }{ \frac{2}{11} - \frac{9}{11} } = - \frac{11}{7}$