Question

сократите дробь

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Answer 1

$frac{(x^2-2xy+y^2)+(zx-zy)}{(z^2-y^2)+(xy+zx)}= frac{(x-y)^2+z(x-y)}{(z-y)(z+y)+x(y+z)}= frac{(x-y)(x-y+z)}{(z+y)(z-y+x)}= \ =frac{(x-y)(x-y+z)}{(z+y)(x-y+z)}=frac{x-y}{z+y}$