因式分解:x2-xy-y2 X平方减XY减Y平方.

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因式分解:x2-xy-y2X平方减XY减Y平方.因式分解:x2-xy-y2X平方减XY减Y平方.因式分解:x2-xy-y2X平方减XY减Y平方.x²-xy-y²=x²-x

因式分解:x2-xy-y2 X平方减XY减Y平方.
因式分解:x2-xy-y2 X平方减XY减Y平方.

因式分解:x2-xy-y2 X平方减XY减Y平方.
x²-xy-y²
=x²-xy+y²/4-5y²/4
=(x-y/2)²-5y²/4
=[x+(√5-1)y][x-(√5+1)y]

x2-xy-y2 =1/4*[2x-(1+√5)y][2x-(1-√5)y]

x^2-xy-y^2
=1/4(4x^2-4xy-4y^2)
=1/4[(4x^2-4xy+y^2)-5y^2]
=1/4[(2x-y)^2-5y^2]
=1/4(2x-y+根号5y)(2x-y-根号5y)
=1/4[2x-(1-根号5)y][2x-(1+根号5)y]