Question

помогите (много баллов!)

Answer 1

$frac{b}{a - b} - frac{ {a}^{3} - a {b}^{2} }{ {a}^{2} + {b}^{2} } times ( frac{a}{ {(a - b)}^{2} } - frac{b}{ {a}^{2} - {b}^{2} })= frac{b}{a - b} - frac{ {a}( {a}^{2} - {b}^{2}) }{ {a}^{2} + {b}^{2}} times frac{ {a}^{2} + {b}^{2} }{ {(a - b)}^{2} (a + b)} = frac{b}{a - b} - frac{a}{a - b} = frac{b - a}{a - b} = - 1$