1若(1/a)+(1/b)=1/(a+b),则(b/a)+(a/b)=?(2)计算;(2008×2007^2+2007)/(2008×2006^2+2008^3-2)
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1若(1/a)+(1/b)=1/(a+b),则(b/a)+(a/b)=?(2)计算;(2008×2007^2+2007)/(2008×2006^2+2008^3-2)
1若(1/a)+(1/b)=1/(a+b),则(b/a)+(a/b)=?(2)计算;(2008×2007^2+2007)/(2008×2006^2+2008^3-2)
1若(1/a)+(1/b)=1/(a+b),则(b/a)+(a/b)=?(2)计算;(2008×2007^2+2007)/(2008×2006^2+2008^3-2)
1.
1/a+1/b=(a+b)/ab=1/(a+b)
ab=(a+b)^2
ab=a^2+b^2+2ab
a^2+b^2=-ab
b/a+a/b=(b^2+a^2)/ab=-ab/ab=-1
2.
分母=2008*(2006^2+2008^2)-2
=2008*[(2007-1)^2+(2007+1)^2]-2
=2008*(2007^2-2*2007+1+007^2+2*2007+1)
=2008*(2*2007^2+2)-2
=2*2008*2007^2+2*2008-2
=2*2008*2007^2+2*(2008-1)
=2*2008*2007^2+2*2007
=2*(2008*2007^2+2007)
=2*分子
所以原式=1/2