tinh: ( 1/52+ 1/51+ 1/53 + ...+ 1/100) : ( 1/1.2 + 1/3.4 + 1/5.6 + .... + 1/99.100 )
tinh: ( 1/52+ 1/51+ 1/53 + ...+ 1/100) : ( 1/1.2 + 1/3.4 + 1/5.6 + .... + 1/99.100 )
CHỨNG MINH:1/1.2+1/3.4+1/5.6+1/7.8+.......+1/99.100=1/51+1/52+1/53+......+1/100
Cho A = 1/51 + 1/52+ 1/53 +...+ 1/100
B = 1/1.2 + 1/3.4 +1/5.6+...+ 1/99.100
A/ B = ?
Tính E=\(\frac{\frac{1}{51}+\frac{1}{52}+\frac{1}{53}+....+\frac{1}{100}}{\frac{1}{1.2}+\frac{1}{3.4}+\frac{1}{5.6}+....+\frac{1}{99.100}}\)
Tính \(E=\frac{\frac{1}{51}+\frac{1}{52}+\frac{1}{53}+....+\frac{1}{100}}{\frac{1}{1.2}+\frac{1}{3.4}+\frac{1}{5.6}+..+\frac{1}{99.100}}\)
Cho A = 1/51 + 1/52+ 1/53 +...+ 1/100
B = 1/1.2 + 1/3.4 +1/5.6+...+ 1/99.100
A/ B = ? (chi tiết nha)
A=1/1.2+1/3.4+1/5.6+....+1/97.98+1/99.100 B=1/50+1/51+1/52+....+1/99+1/100 Tính A-B
Cho A = 1/1.2+1/3.4+1/5.6+...+1/99.100
a Chứng minh A= 1/51+1/52+1/53+...+1/100
b Chứng minh 7/12<A<5/6