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来源:学生作业帮助网 编辑:作业帮 时间:2024/05/04 13:17:23
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(x+1-x)(a^/x+b^/(1-x))
=a^2+b^2+b^2*x/(1-x)+a^2*(1-x)/x
>=a^2+b^2+2ab
=(a+b)^2

y= [x+(1-x)][a^/x+b^/(1-x)]
=a+b+a(1-x)/(x+b)+bx/(1-x)
≥a+b+2√a(1-x)/(x+b)*bx/(1-x)
=a+b+2√ab=(√a+√b)^2
当x=1-x即x=1/2时取等号
题目中应是a,b为正数