if you are good at math,please…1.a,b,c都为正数,满足c/(a+b)<a/(b+c)<b/(c+a),求a,b,c的大小关系.2.实数a,b,c满足条件a+b+c=9,求代数式(a-b)+(c-b)+(c-a)的最大值
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![if you are good at math,please…1.a,b,c都为正数,满足c/(a+b)<a/(b+c)<b/(c+a),求a,b,c的大小关系.2.实数a,b,c满足条件a+b+c=9,求代数式(a-b)+(c-b)+(c-a)的最大值](/uploads/image/z/9130433-41-3.jpg?t=if+you+are+good+at+math%2Cplease%E2%80%A61.a%2Cb%2Cc%E9%83%BD%E4%B8%BA%E6%AD%A3%E6%95%B0%2C%E6%BB%A1%E8%B6%B3c%2F%EF%BC%88a%2Bb%EF%BC%89%EF%BC%9Ca%2F%EF%BC%88b%2Bc%EF%BC%89%EF%BC%9Cb%2F%EF%BC%88c%2Ba%EF%BC%89%2C%E6%B1%82a%2Cb%2Cc%E7%9A%84%E5%A4%A7%E5%B0%8F%E5%85%B3%E7%B3%BB.2.%E5%AE%9E%E6%95%B0a%2Cb%2Cc%E6%BB%A1%E8%B6%B3%E6%9D%A1%E4%BB%B6a%2Bb%2Bc%3D9%2C%E6%B1%82%E4%BB%A3%E6%95%B0%E5%BC%8F%EF%BC%88a-b%EF%BC%89%2B%EF%BC%88c-b%EF%BC%89%2B%EF%BC%88c-a%EF%BC%89%E7%9A%84%E6%9C%80%E5%A4%A7%E5%80%BC)
if you are good at math,please…1.a,b,c都为正数,满足c/(a+b)<a/(b+c)<b/(c+a),求a,b,c的大小关系.2.实数a,b,c满足条件a+b+c=9,求代数式(a-b)+(c-b)+(c-a)的最大值
if you are good at math,please…
1.a,b,c都为正数,满足c/(a+b)<a/(b+c)<b/(c+a),求a,b,c的大小关系.2.实数a,b,c满足条件a+b+c=9,求代数式(a-b)+(c-b)+(c-a)的最大值
if you are good at math,please…1.a,b,c都为正数,满足c/(a+b)<a/(b+c)<b/(c+a),求a,b,c的大小关系.2.实数a,b,c满足条件a+b+c=9,求代数式(a-b)+(c-b)+(c-a)的最大值
c/(a+b)c(b+c)a^2-c^2+ab-bc>0-->(a-c)(a+b+c)>0-->a>c a/(b+c)a(a+c)b^2-a^2+bc-ac>0-->(b-a)(a+b+c)>0-->b>a b>a>c (a-b)^2+(c-b)^2+(c-a)^2=2(a^2+b^2+c^2-ab-bc-ca)=2(9-ab-bc-ca) 9=a^2+b^2+c^2>=-(ab+bc+ca)-->-(ab+bc+ca)
1因为c/(a+b)<a/(b+c)<b/(c+a) a,b,c都为正数 所以c/(a+b)+1<a/(b+c)+1<b/(c+a)+1 所以(a+b+c)/(a+b)<(a+b+c)/(b+c)<(a+b+c)/(c+a) 所以1/(a+b)<1/(b+c)<1/(c+a) 所以a>c>b 2 因为(a+b)≥0 所以-2ab≤a+b (a-b)=a+b-2ab≤2(a+b) 所以(a-b)+(...
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1因为c/(a+b)<a/(b+c)<b/(c+a) a,b,c都为正数 所以c/(a+b)+1<a/(b+c)+1<b/(c+a)+1 所以(a+b+c)/(a+b)<(a+b+c)/(b+c)<(a+b+c)/(c+a) 所以1/(a+b)<1/(b+c)<1/(c+a) 所以a>c>b 2 因为(a+b)≥0 所以-2ab≤a+b (a-b)=a+b-2ab≤2(a+b) 所以(a-b)+(c-b)+(c-a)≤2(a+b)+2(c+b)+2(a+c)≤36 最大值为36
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