tag:blogger.com,1999:blog-6678396372832075291.post7509242938735477953..comments2024-03-28T08:42:44.169+07:00Comments on Học Để Thi: Tuyển tập bài bất đẳng thứcTrang Anh Namhttp://www.blogger.com/profile/15065197607659721471noreply@blogger.comBlogger29125tag:blogger.com,1999:blog-6678396372832075291.post-27785123878370440062017-11-29T20:43:28.880+07:002017-11-29T20:43:28.880+07:00a+b+c = 0 => a + b = -c => (a +b)^3 = -c^3 &...a+b+c = 0 => a + b = -c => (a +b)^3 = -c^3 <=> a^3+b^3+ 3ab(a+b) =-c^3<br />mà a+b = -c => a^3+b^3 +c^3 = 3abcNguyễn Nguyệthttps://www.blogger.com/profile/10958087801585754382noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-4086632958762246362017-09-01T13:32:54.696+07:002017-09-01T13:32:54.696+07:00giup em giai bai nay voigiup em giai bai nay voiAnonymoushttps://www.blogger.com/profile/00094771273320937131noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-25975114471415075302015-12-02T20:40:14.185+07:002015-12-02T20:40:14.185+07:00AM-GM ngược dấuAM-GM ngược dấuAnonymoushttps://www.blogger.com/profile/02541437557287217522noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-77498798694551927992015-03-31T20:54:54.706+07:002015-03-31T20:54:54.706+07:00yoloyoloAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-57817486630099584442015-01-13T14:22:31.865+07:002015-01-13T14:22:31.865+07:00Lâu lắm không động tới toán rồi, giờ học đại học t...Lâu lắm không động tới toán rồi, giờ học đại học toàn liên quan tới chuyên ngành.mua thẻ điện thoại onlinehttp://thecao.net/mua-the-dien-thoai/noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-33251587476603518292015-01-05T13:50:07.784+07:002015-01-05T13:50:07.784+07:00Chứng minh rằng |a|+|b|+|c|+|a+ b+ c| ≥ |a+ b|+|b+...Chứng minh rằng |a|+|b|+|c|+|a+ b+ c| ≥ |a+ b|+|b+c| + |c+a| với mọi số thực a, b, c.?Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-3702118124816011092015-01-05T13:45:53.573+07:002015-01-05T13:45:53.573+07:00Cho a, b, c, d > 0 thỏa mãn ab + bc + cd + da =...Cho a, b, c, d > 0 thỏa mãn ab + bc + cd + da =1. Chứng minh bất đẳng thức<br />a³/(b+c+d) + b³/(c+d+a) + c³/(d+a+b) + d³/(a+b+c) ≥ 1/3Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-2219758145200660892015-01-05T13:44:49.267+07:002015-01-05T13:44:49.267+07:00Chứng minh mọi a,b,c>0 ta có 2(a^2+b^2+c^2)+...Chứng minh mọi a,b,c>0 ta có 2(a^2+b^2+c^2)+abc+8>= 5(a+b+c)Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-78234008215244764782015-01-05T13:43:53.886+07:002015-01-05T13:43:53.886+07:00Cho a,b,c >0; a+b+c =3. CMR:
1/( a² +7) +1/( b...Cho a,b,c >0; a+b+c =3. CMR: <br />1/( a² +7) +1/( b² +7) +1/( c² +7) ≤ 1/4. [1/(a+b) +1/(b+c) +1/(c+a)]<br />phải dùng AM-GMTrang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-26218521084562188672015-01-05T13:42:44.438+07:002015-01-05T13:42:44.438+07:00cho 3 số dương a,b,c thoa mãn a^2+b^2+c^2=3.cmr: a...cho 3 số dương a,b,c thoa mãn a^2+b^2+c^2=3.cmr: a/√b + b/√c + c/√a >=ab +bc +acTrang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-1110084293673565212015-01-05T13:41:21.736+07:002015-01-05T13:41:21.736+07:00cho a,b,b>o
CMBĐT : (a/b+c)^3 + (b/a+c)^3 + (c/...cho a,b,b>o<br />CMBĐT : (a/b+c)^3 + (b/a+c)^3 + (c/a+b)^3 >= 3/8Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-35165087059487617972015-01-05T13:40:45.057+07:002015-01-05T13:40:45.057+07:00Cho cac so a,b,c tm : 0< a <=1, 0< b <...Cho cac so a,b,c tm : 0< a <=1, 0< b <= 1<br />Chung minh rang: ( 1+ 1/(abc))(a+b+c) >= 3+ 1/a + 1/b + 1/cTrang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-17092566712884806532015-01-05T13:39:09.694+07:002015-01-05T13:39:09.694+07:00cho ab+a+b=3, chung minh 3a/(b+1)+3b/(a+1) +ab/(a+...cho ab+a+b=3, chung minh 3a/(b+1)+3b/(a+1) +ab/(a+b) <= a^2+b^2+3/2Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-82750202302797846612015-01-05T13:34:19.215+07:002015-01-05T13:34:19.215+07:00Cho a + b <= 1, cm ( a + 2/b )^2 + ( b + 2/a )^...Cho a + b <= 1, cm ( a + 2/b )^2 + ( b + 2/a )^2 >= 81/2Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-86623031990010365672015-01-05T13:33:09.945+07:002015-01-05T13:33:09.945+07:00Cho 3 số a, b c dương .chứng minh rằng
1/(a^3 + b^...Cho 3 số a, b c dương .chứng minh rằng<br />1/(a^3 + b^3 +abc) + 1/(b^3 +c^3+abc) +1/(c^3 +a^3+abc)<= 1/abcTrang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-92020789994882589312015-01-05T13:32:23.307+07:002015-01-05T13:32:23.307+07:00CMR: 1/(a+b)+1/(b+c)+1/(c+a)≥4/(a^2+7)+4/(b^2+7)+4...CMR: 1/(a+b)+1/(b+c)+1/(c+a)≥4/(a^2+7)+4/(b^2+7)+4/(c^2+7)<br />với a,b,c dương thỏa mãn a^2 +b^2 +c^2 =3Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-62650649688686263802015-01-05T13:31:07.569+07:002015-01-05T13:31:07.569+07:00Tim min cua (a+b)/[ab(1-a-b)] biet 1>a+b va a,b...Tim min cua (a+b)/[ab(1-a-b)] biet 1>a+b va a,b>0Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-58800103095441923432015-01-05T13:30:24.413+07:002015-01-05T13:30:24.413+07:00Cho a,b,c là các số thực dương thoã mãn: a^2 + b^2...Cho a,b,c là các số thực dương thoã mãn: a^2 + b^2 + c^2 = 3.<br />Chứng minh rằng: <br />[4:(a^2 + b^2) +1].[4:(b^2 + c^2) +1].[4:(c^2 + a^2) +1] >= 3.(a + b + c)^2Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-38092541511642581172015-01-05T13:28:50.449+07:002015-01-05T13:28:50.449+07:00CMR can (a/(b+c))+can (b/(a+c))+can (c/(b+a))>2...CMR can (a/(b+c))+can (b/(a+c))+can (c/(b+a))>2 voi a,b,c>0?Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-18533771725908145832015-01-05T13:28:14.321+07:002015-01-05T13:28:14.321+07:00Cho a + b + c = 0 . Chứng minh rằng a^3 + b^3 + ...Cho a + b + c = 0 . Chứng minh rằng a^3 + b^3 + c^3 = 3abc?Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-87818800024645938372015-01-05T13:27:19.319+07:002015-01-05T13:27:19.319+07:00CMR a/(a+b+c) + b/(b+c+d) + c/(c+d+a) + d/(d+a+b) ...CMR a/(a+b+c) + b/(b+c+d) + c/(c+d+a) + d/(d+a+b) không thuộc Z với a,b,c,d là số nguyên dương?Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-45634120397097754302015-01-05T13:27:03.069+07:002015-01-05T13:27:03.069+07:00CM BĐT 1/(a+b+1) +1/(b+c+1) +1/(c+a+1) =< 1 cho...CM BĐT 1/(a+b+1) +1/(b+c+1) +1/(c+a+1) =< 1 cho abc=1 a,b,c>0Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-20845303835346572062015-01-05T13:25:25.514+07:002015-01-05T13:25:25.514+07:00Cho a b c là 3 cạnh của 1 tam giác
a. cm a/(b+c-a...Cho a b c là 3 cạnh của 1 tam giác <br />a. cm a/(b+c-a) + b/(a+c-b) + c/(a+b-c) >= 3<br />b. CMR 1< a/(b+c) + b/(a+c) + c/(a+b) <2<br />c. cmr: a²/(b+c-a)+b²/(c+a-b)+c²/(a+b-c) >= a+b+c<br />d. 1/(a+b-c)+ 1/(b +c-a) +1/(c+a -b) >=1/a +1/b+1/c<br />e. CMR (a+b-c)(a-b+c)(-a+b+c)<=abc<br />f. a(b-c)^2 + b(c-a)^2 + c(a-b)^2 > a^3 + b^3 + c^3<br />g. cmr: x^2 + (a+b+c)x+ab+bc+ac Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-16098307290354182022015-01-05T13:12:49.743+07:002015-01-05T13:12:49.743+07:00Cho a,b,c thuộc [0;1]. CMR: a/(b+c+1) +b/(a+c+1) +...Cho a,b,c thuộc [0;1]. CMR: a/(b+c+1) +b/(a+c+1) +c/(a+b+1) +(1-a) .(1-b).(1-c) <=1?Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.comtag:blogger.com,1999:blog-6678396372832075291.post-44936168670116927552015-01-05T13:12:20.490+07:002015-01-05T13:12:20.490+07:001) Cho a,b,c#0 và 1/a+1/b+1/c=0.CM:bc/a² +ca/b² + ...1) Cho a,b,c#0 và 1/a+1/b+1/c=0.CM:bc/a² +ca/b² + ab/c²=3?<br />2)x,y>0,x²+y²=1.Tìm GTNN:(1+x)(1+ 1/y)+(1+y)(1+ 1/x) <br />3)a,b,c>0,a+b+c=6abc.CM:bc/a³(c+2b) +ca/b³(a+2c) +ab/c³(b+2a)≥ 2Trang Anh Namhttps://www.blogger.com/profile/00292971774782720829noreply@blogger.com