农业银行卡修改密码:数学题急急急

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(x+y/2)^2-(x-y/2)^2

求过程

(x+y/2)^2-(x-y/2)^2
=(x+y/2+x-y/2)(x+y/2-x+y/2) (平方差公式)
=2x*y
=2xy

(x+y/2)^2-(x-y/2)^2

=(x+y/2+x-y/2)x( x+y/2-x+y/2)
=2xy

(x+y/2)^2-(x-y/2)^2
=(x+y/2+x-y/2)(x+y/2-x+y/2) (平方差公式)
=2xy

(x+y/2)^2-(x-y/2)^2
=(x+y/2+x-y/2)(x+y/2-x+y/2) (平方差公式)
=2x*y
=2xy

(x+y/2+x-y/2)*(x+y/2-x+y/2)=2xy