Các câu hỏi tương tự
Cho A = 3/5 + 11/13 + 23/25 + ... + 19799/19801. CM: A>98.
\(A=\frac{155-\frac{10}{7}-\frac{5}{11}+\frac{5}{23}}{403-\frac{26}{7}-\frac{13}{11}+\frac{13}{23}}+\frac{\frac{3}{5}+\frac{3}{13}-0,9}{\frac{7}{91}+0,2-\frac{3}{10}}\)
Chứng minh:
c.\(\frac{11}{15}< \frac{1}{21}+\frac{1}{22}+\frac{1}{23}+...+\frac{1}{59}+\frac{1}{60}< \frac{3}{2}\)
b.\(\frac{1}{5}+\frac{1}{13}+\frac{1}{25}+\frac{1}{41}+\frac{1}{61}+\frac{1}{85}+\frac{1}{113}< \frac{1}{2}\)
a.\(\frac{1}{4}+\frac{1}{16}+\frac{1}{36}+\frac{1}{64}+\frac{1}{100}+\frac{1}{144}+\frac{1}{196}< \frac{1}{2}\)
1. cho A = \(\frac{4}{3}+\frac{7}{3^2}+\frac{10}{3^3}+...+\frac{301}{3^{100}}\)chứng minh: A< \(\frac{11}{4}\)
2. cho B = \(\frac{11}{3}+\frac{17}{3^2}+\frac{23}{3^3}+...+\frac{605}{3^{100}}\)chứng minh: B<7
3. cho C = \(\frac{4}{3}+\frac{13}{3^2}+\frac{22}{3^3}+...+\frac{904}{3^{101}}\)chứng minh: C<\(\frac{17}{4}\)
a)\(\frac{-5}{7}.\left(\frac{2}{11}+\frac{9}{5}\right)+\left(\frac{-9}{11}+\frac{4}{5}\right).\frac{5}{7}\) b)\(2\frac{2}{5}.\frac{5}{9}+1\frac{4}{9}.\frac{12}{5}-1,8.\frac{10}{3}\)c)\(\frac{-7}{25}.\frac{11}{13}+\frac{-7}{25}.\frac{4}{13}-\frac{2}{13}.\frac{-7}{25}\)
Chứng minh
\(\frac{1}{5}+\frac{1}{13}+\frac{1}{25}+....+\frac{1}{10^2+11^2}<\frac{9}{20}\)
Tính :
a) \(\frac{6}{14}+\frac{8}{-36}-\frac{5}{35}=\)
b) \(\frac{31}{23}-\left(\frac{7}{32}+\frac{8}{23}\right)\)
c) \(\frac{10}{17}+\frac{5}{13}+\frac{-7}{17}-\frac{8}{13}+\frac{11}{25}\)
9 tháng 2 2019 lúc 9:09
Giải giùm mk zới mn~~~~tặng người đầu tiên làm 4 tick nha(đảm bảo lên 4 điểm 100%)a)frac{-4}{9}.frac{7}{15}+frac{4}{-9}.frac{8}{15}b)frac{5}{-4}.frac{16}{25}+frac{-5}{4}.frac{9}{25}.c)4frac{11}{23}-frac{9}{14}+2frac{12}{23}-frac{5}{4}.d)2frac{13}{27}-frac{7}{15}+3frac{14}{27}-frac{8}{15}e)11frac{1}{4}-left{2frac{5}{7}+5frac{1}{4}right}g)frac{7}{19}.frac{8}{11}+frac{7}{19}.frac{3}{11}+frac{12}{19}
Đọc tiếp
Giải giùm mk zới mn~~~~tặng người đầu tiên làm 4 tick nha(đảm bảo lên 4 điểm 100%)
a)\(\frac{-4}{9}.\frac{7}{15}+\frac{4}{-9}.\frac{8}{15}\)
b)\(\frac{5}{-4}.\frac{16}{25}+\frac{-5}{4}.\frac{9}{25}.\)
c)\(4\frac{11}{23}-\frac{9}{14}+2\frac{12}{23}-\frac{5}{4}.\)
d)\(2\frac{13}{27}-\frac{7}{15}+3\frac{14}{27}-\frac{8}{15}\)
e)\(11\frac{1}{4}-\left\{2\frac{5}{7}+5\frac{1}{4}\right\}\)
g)\(\frac{7}{19}.\frac{8}{11}+\frac{7}{19}.\frac{3}{11}+\frac{12}{19}\)
a )-\(-\frac{17}{30}-\frac{11}{-15}+-\frac{7}{12}\)
b ) \(-\frac{5}{9}+\frac{5}{9}:\left(1\frac{2}{3}-2\frac{1}{12}\right)\)
c ) \(-\frac{7}{25}.\frac{11}{13}+-\frac{7}{25}.\frac{2}{13}-\frac{18}{25}\)