【(x+2y)的平方-(x-2y)的平方-(x+2y)(x-2y)-4y】÷2x 已知x的平方+y的平方-4X+y+4分
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【(x+2y)的平方-(x-2y)的平方-(x+2y)(x-2y)-4y】÷2x

=(x²+4xy+4y²-x²+4xy-4y²-x²+4y²-4y)÷2x

=(-x²+8xy+4y²-4y)÷2x

x的平方+y的平方-4X+y+4分之17=0

x²-4x+4+y²+y+1/4-4-1/4+17/4=0

(x-2)²+(y+1//2)²=0

(x-2)²=0 (y+1/2)=0

x=2 y=-1/2

把x=2 y=-1/2代人化简式得:

[-2²+8×2×(-1/2)+4×(-1/2)-4×(-1/2)]÷(2×2)

=(-4+8-2+2)÷4

=4÷4

=1