Помогите пожалуйста. алгебра. легко. забыла
(x+y - x-y ) * x-y = (x-y x+y) 2y = (x+y)² - (x-y)² * x-y = (x-y)(x+y) 2y = x²+2xy+y²-x²+2xy-y² * x-y = (x-y)(x+y) 2y = 4xy * x-y = (x-y)(x+y) 2y = 2x x+y
=x^2+2xy+y^2-x^2+2xy-y^2 / (x-y)(x+y) * x-y/2y = 4xy/(x-y)(x+y) * x-y/2y => (x-y) сокращаем 4xy/x+y * 1/2y = 2x/x+y