Các câu hỏi tương tự
Chứng minh :
1,C=\(\frac{1}{11}+\frac{1}{12}+\frac{1}{13}+...+\frac{1}{70}.C< \frac{3}{4}\)
2,D=\(\frac{1}{5^2}+\frac{1}{9^2}+...+\frac{1}{409^2}< \frac{1}{12}\)
3,E=\(\frac{5}{5.8.11}+\frac{5}{8.11.14}+...+\frac{5}{302.305.308}< \frac{1}{48}\)
Cho B=5/5.8.11+5/8.11.14+...+5/302.305.308
Chứng minh B<1/48
cho c=5/5.8.11+5/8.11.14+5/302.305.308
c/m : c <1/48
C=5/58.11+5/8.11.14+3.6/4.5+...+5/302.305.308 CMR C<1/48
1. A = \(\frac{1}{2}-\frac{1}{3}+\frac{1}{4}-\frac{1}{5}+...+\frac{1}{48}-\frac{1}{49}\)
Chứng minh rằng: \(\frac{1}{5}< A< \frac{2}{5}\)
Cho C = \(\frac{5}{4}+\frac{5}{4^2}+\frac{5}{4^3}+...+\frac{5}{4^{99}}.\)Chứng minh rằng C <\(\frac{5}{3}\)
Cho C =\(\frac{5}{4}+\frac{5}{4^2}+\frac{5}{4^3}+...+\frac{5}{4^{99}}\)
Chứng minh C <\(\frac{5}{3}\)
Cho C= \(\frac{5}{4}+\frac{5}{4^2}+\frac{5}{4^3}+..+\frac{5}{4^{99}}\) Chứng minh C<5/3
chứng minh rằng A =\(\frac{1}{4}.\frac{3}{6}.\frac{5}{8}.....\frac{43}{46}.\frac{45}{48}\)<\(\frac{1}{133}\)