因式分解a^2+ab+b+a x+y=1,xy=1/5,求(x^2+1)(y^2+1)

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因式分解a^2+ab+b+ax+y=1,xy=1/5,求(x^2+1)(y^2+1)因式分解a^2+ab+b+ax+y=1,xy=1/5,求(x^2+1)(y^2+1)因式分解a^2+ab+b+ax+

因式分解a^2+ab+b+a x+y=1,xy=1/5,求(x^2+1)(y^2+1)
因式分解a^2+ab+b+a x+y=1,xy=1/5,求(x^2+1)(y^2+1)

因式分解a^2+ab+b+a x+y=1,xy=1/5,求(x^2+1)(y^2+1)
1.原式=a(a+b)+(a+b)
=(a+1)(b+1)
2.原式=x^2y^2+x^2+y^2+1
=(xy)^2+(x+y)^2-2xy+1
代入,原式=1\25+1-2\5+1
=41\25

解1:
a²+ab+b+a
=a(a+b)+a+b
=(a+b)(a+1)

解2:
x+y=1,xy=1/5,
(x²+1)(y²+1)=(xy)²+x²+y²+1
=(xy)²+x²+2xy+y²-2xy+1
=(xy)²...

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解1:
a²+ab+b+a
=a(a+b)+a+b
=(a+b)(a+1)

解2:
x+y=1,xy=1/5,
(x²+1)(y²+1)=(xy)²+x²+y²+1
=(xy)²+x²+2xy+y²-2xy+1
=(xy)²+(x+y)²-2xy+1
=(xy)²-2xy+1+(x+y)²
=(xy-1)²+(x+y)²
=[(1/5)-1]²+(1)²
=(-4/5)²+1
=41/25
=1.64

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