\(\dfrac{1}{2\cdot6}+\dfrac{1}{3\cdot8}+...+\dfrac{1}{2023\cdot4048}\)
\(=\dfrac{2}{4\cdot6}+\dfrac{2}{6\cdot8}+...+\dfrac{2}{4046\cdot4048}\)
\(=\dfrac{1}{4}-\dfrac{1}{6}+\dfrac{1}{6}-\dfrac{1}{8}+...+\dfrac{1}{4046}-\dfrac{1}{4048}\)
\(=\dfrac{1}{4}-\dfrac{1}{4048}=\dfrac{1011}{4048}\)
Giúp em với cần gấp lắm :
T= \(\dfrac{1}{2.6}+\dfrac{1}{3.8}+\dfrac{1}{4.10}+\dfrac{1}{5.12}+...+\dfrac{1}{1-11.2014}\)
Chứng minh rằng:
A=3/1.4+3/2.6+3/3.8+..............+1/2012.1342<1,5
Chứng minh rằng \(\frac{3}{1.4}+\frac{3}{2.6}+\frac{3}{3.8}+...+\frac{1}{2012.1342}\)<1.5
Chứng minh rằng:A=\(\frac{3}{1.4}\)+\(\frac{3}{2.6}\)+\(\frac{3}{3.8}\)+....+\(\frac{1}{2012.1342}\)<1;5
chứng minh rằng: A= 3/1.4+ 3/2.6+ 3/3.8+ ...+ 3/2012.1342 <1,5
chứng minh rang A=3/1.4+3/2.6+3/3.8+...+3/2012.4046<1,5
Tìm x
a, (x-2)^5=(x-2)^3
b,(x-3)^3=(x-3)^2 c,11.6^x-1+2.6^x+1 =11.6^11+2.6^13
d, 6.8^x-1+8^x-1=6.8^19+8^21
CMR:1/28+1/30+1/32+1/34+...+1/52=1/1.4+1/3.8+1/5.12+1/7.16+...+1/25.52
2023-1/2.6-1/4.9-1/6.12-...-1/36.57-1/38.60
Cho A=1/1.4+1/3.8+1/5.12+...+1/99.200
CMR:A<5/12
