计算:5x的平方-4xy分之x的平方-y的平方÷5x-4y分之x y
问题描述:
计算:5x的平方-4xy分之x的平方-y的平方÷5x-4y分之x y
答
(x²-y²)/(5x²-4xy)÷(x+y)/(5x-4y)
=(x+y)(x-y)/x(5x-4y)*(5x-4y)/(x+y)
=(x-y)/x