1 phần 1. 2 + 1phan 2.3 + 1 phan 3.4+...............+ 1phan 98.99 +1phan 99.100
1- 1 phan 2 - 1 phan 2 ^2 - 1phan 2^3 - 1phan 2^4-....- 1phan 2^10 .> 1phan 2^11
1phan 2 cong 1phan 6 cong 1 phan 12 cong 1phan 20 cong 1phan 30 cong mot phan 42 cong mot phan 56 cong mot phan 72 =????
(1phan 2x4+1 phan 4x6+1 phan 6x8+1phan 8x10)xy 1phan 3
dien dau <,>,=
1phan2+ 1phan4... 1
1phan 5+ 2 phan 13...1
1phan 12+ 2 phan 14 ...1
1phan 2 +2phan 3... 1
1phan2+ 1phan4 < 1
1phan 5+ 2 phan 13 < 1
1phan 12+ 2 phan 14 < 1
1phan 2 +2phan 3 > 1
chung minh :1phan 11 mu 2 + 1phan 12mu 2 + 1 phan 13 mu2+..........+1 phan 100 mu2 <9phan100 chi giup voi quen cach lam roi
Cho a=1 Phan 11 +1phan 12+1phan 13+...+1phan 70
Chứng minh A>4phan 3
Tinh
1phan 2 +1 phan 3 + 1 phan 6
\(\frac{1}{2}+\frac{1}{3}+\frac{1}{6}=\frac{3+2+1}{6}=\frac{6}{6}=1\)
\(\frac{1}{2}+\frac{1}{3}+\frac{1}{6}=\frac{3}{6}+\frac{2}{6}+\frac{1}{6}=\frac{6}{6}=1\)
\(\frac{1}{2}\)+\(\frac{1}{3}\)+\(\frac{1}{6}\)=\(\frac{3}{6}\)+\(\frac{2}{6}\)+\(\frac{1}{6}\)=\(\frac{5}{6}\)+\(\frac{1}{6}\)=\(\frac{6}{6}\)=1
1phan 2 cong 1 phan 3 cong 1 phan 5 bang bao nhieu
\(\frac{1}{2}+\frac{1}{3}+\frac{1}{5}=\frac{31}{30}\)
1so sanh phan so
12/25 va 25/49 80/95 va 144/153
6 tinh gia tri bieu thucphanso
1phan 72+1phan56+1 phan 42+ 1phan 30 +1phan 20 + 1phan 12
7tinh nhanh phan so
17 phan 12+ 9phan 7-(2phan7 -7phan 12)
11phan7 nhan (38 phan 45 nhan 17 phan 11 )
(1+1phan2 ) nhan (1+1phan3 ) nhan ....... nhan (1+1phan2005
9 cho phan so 25phan 42 tim so tu nhien a sao cho khi them vao tu so cua phan so da cho va giu nguyen mau so thi duoc phan so moi bang 6phan 7