Question

Сократить дробь
$frac{ {y}^{2} - {z}^{2} }{(z - y) {}^{2} }$

Answer 1

$frac{ {y}^{2} - {z}^{2} }{(z - y) {}^{2} } = frac{ (y-z)(y+z)}{(-1*(y - z))^{2} } = frac{ (y-z)(y+z)}{(y - z)^{2} } = frac{y+z}{y - z}$