Các câu hỏi tương tự
bai1 cho a/b=c/d voi a,b,c,d la nhung so tu nhien khác 0 CMR (a,d)/(b,c)=[b,c]/[a,d]
Cho a, b, c, d la cac so nguyen duong thoa man a2+b2=b2+d2. CM a+b+c+d la hop so
cho 4 duong thang a,b,c,d sao cho a song song voi b .c song song voi d; c cat a so cap goc so le trong tao thanh la
ai giup cho like
Cho a, b, c, d la cac so nguyen duong thoa man a + b=c + d= 25
Tim GTLN cua M = \(\frac{c}{b}\)+ \(\frac{d}{a}\)
Cho 4 so nguyen duong a,b,c,d ma trong do b la trung binh cong cua 2 so a va c.Chung minh rang 4 so a,b,c,d lap thanh mot ti le thuc neu \(\frac{2}{c}\)=\(\frac{1}{b}+\frac{1}{d}\)
cho a, b, c, d la 4 so nguyen duong thoa man: b= \(\frac{a+c}{2}va\frac{1}{c}=\frac{1}{2}.\left(\frac{1}{b}+\frac{1}{d}\right)\)
chung minh: \(\frac{a}{b}=\frac{c}{d}\)
B1: cho a,b,c la cac so nguyen duong
CMR:neu a /b >hoac bang c/d thi a/b > hoac bang a+c/b+d > hoac bang c/d
B2: Tim PS nho nhat khac 0 sao cho khi chia no cho 14/9 ; cho 45/27 deu duoc thuong la cac so tu nhien
B3:CMR: 1/2^2 + 1/4^2 + 1/6^2 +....+ 1/100^2 < 1/2
CHO a,b,c,d LA CAC SO DUONG CMR
1 < a/(a+b+c) + b/(b+c+d) + c/(c+d+a) + d/(d+a+b) < 2
CHO a,b,c,d LA CAC SO DUONG CMR
1 < a/(a+b+c) + b/(b+c+d) + c/(c+d+a) + d/(d+a+b) < 2