分解因式(x+y)2-8(x2-y2)+16(x-y)22指的是平方

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分解因式(x+y)2-8(x2-y2)+16(x-y)22指的是平方

分解因式(x+y)2-8(x2-y2)+16(x-y)22指的是平方
分解因式(x+y)2-8(x2-y2)+16(x-y)2
2指的是平方

分解因式(x+y)2-8(x2-y2)+16(x-y)22指的是平方
(x+y)2-8(x2-y2)+16(x-y)2
=[x+y]^2-8[x+y][x-y]+16[x-y]^2
=[(x+y)-4(x-y)]^2
=[-3x+5y]^2

(x+y)2-8(x2-y2)+16(x-y)2
=(x+y)2-8(x-y)(x+y)+16(x-y)2
设x+y=s,x-y=t
原式=s^2-8st+16T^2
=(s-4t)^2
=(x+y-4x+4y)^2
=(5y-3x)^2

(x+y)²-8(x²-y²)+16(x-y)²
=x²+2xy+y²-8x²+16xy+8y²+16x²-32xy+16y²
=9x²-30xy+25y²
=(3x-5y)²