(2x-y)²-(2x+y)²,
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(2x-y)²-(2x+y)²,
(2x-y)²-(2x+y)²,
(2x-y)²-(2x+y)²,
平方差
原式= (2x-y+2x+y)(2x-y-2x-y)
=4x(-2y)
=-8xy
(2x-y)²-(2x+y)² =(4x2-4xy+y2)-(4x2+4xy+y2)=-8xy
(2x-y)²-(2x+y)²,
(2x-y)²-(2x+y)²,
(2x-y)²-(2x+y)²,
平方差
原式= (2x-y+2x+y)(2x-y-2x-y)
=4x(-2y)
=-8xy
(2x-y)²-(2x+y)² =(4x2-4xy+y2)-(4x2+4xy+y2)=-8xy