【(x+2y)(x-2Y)-(x-2y)²】÷4Y,其中x=2,y=½

问题描述:

【(x+2y)(x-2Y)-(x-2y)²】÷4Y,其中x=2,y=½

【(x+2y)(x-2Y)-(x-2y)²】÷4Y
=(x-2y)[(x+2y)-(x-2y)]
=(x-2y)×4y
=(2-2×½﹚×4×½
=1×2
=2