\(=\dfrac{52}{9}\)
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Tính:
\(A=\frac{\frac{2}{39}-\frac{1}{15}-\frac{2}{153}}{\frac{1}{34}+\frac{3}{20}-\frac{3}{26}}:\frac{1+\frac{2}{71}-\frac{5}{121}}{\frac{65}{121}-\frac{26}{71}-13}\)
THỰC HIỆN:
A=\(\frac{\frac{2}{39}-\frac{1}{15}-\frac{2}{153}}{\frac{1}{34}+\frac{3}{20}-\frac{3}{26}}:\frac{1+\frac{2}{71}-\frac{5}{121}}{\frac{65}{121}-\frac{26}{121}-13}\)
\(1.a.\frac{3}{4}.\frac{1}{210}-\frac{1}{21}.\frac{6}{5}.\frac{1}{4}\)
\(b.\frac{85}{26}:0,185-\frac{59}{26}:0.185\)\(c.2+\frac{2}{2+\frac{2}{2+\frac{2}{2+\frac{1}{2}}}}\)
tính
a, A=\(\frac{1}{90}-\frac{1}{72}-\frac{1}{56}-\frac{1}{42}-\frac{1}{30}-\frac{1}{20}-\frac{1}{12}-\frac{1}{6}-\frac{1}{2}\)
b, B=\(\left(\frac{1}{4}-1\right)\left(\frac{1}{9}-1\right)...\left(\frac{1}{100}-1\right)\left(\frac{1}{121}-1\right)\)
c,C=\(\frac{3}{1.4}+\frac{5}{4.9}+\frac{7}{9.16}+\frac{9}{16.25}+\frac{11}{25.36}\)
Tính giá trị biểu thức:
A = \(\frac{15}{34}+\frac{7}{21}+\frac{9}{34}-1\frac{15}{17}+\frac{2}{3}\) B = \(16\frac{2}{7}:\left(-\frac{3}{5}\right)-28\frac{2}{7}:\left(-\frac{3}{5}\right)\)
C = 25.\(\left(-\frac{1}{3}\right)^3+\frac{1}{5}-2.\left(-\frac{1}{2}\right)^2-\frac{1}{2}\)
A = \(\frac{\frac{1}{11}-\frac{1}{13}-\frac{1}{17}}{\frac{5}{11}-\frac{5}{13}-\frac{5}{17}}+\frac{\frac{2}{3}-\frac{2}{9}-\frac{2}{27}+\frac{2}{81}}{\frac{7}{3}-\frac{7}{9}-\frac{7}{27}+\frac{7}{81}}\)
B = \(\frac{5^2}{11.16}+\frac{5^2}{16.21}+\frac{5^2}{21.26}+\frac{5^2}{26.31}+...+\frac{5^2}{56.81}\)
C = \(1-\frac{1}{3}-\frac{1}{6}-\frac{1}{10}-\frac{1}{15}-...-\frac{1}{1225}\)
Tính nhanh:
a) A=\(\frac{1}{3}-\frac{3}{4}-\left(-\frac{3}{5}\right)+\frac{1}{72}-\frac{2}{9}-\frac{1}{36}+\frac{2}{15}\)b) B=\(\frac{1}{5}-\frac{3}{7}+\frac{5}{9}-\frac{2}{11}+\frac{7}{13}-\frac{9}{16}-\frac{7}{13}+\frac{2}{11}-\frac{5}{9}+\frac{3}{7}-\frac{1}{5}\)c) C= \(\frac{1}{100}-\frac{1}{100.99}-\frac{1}{99.98}-...-\frac{1}{3.2}-\frac{1}{2.1}\)
1) Tính:a) frac{left(1+frac{17}{1}right).left(1+frac{17}{2}right).left(1+frac{17}{3}right).....left(1+frac{17}{19}right)}{left(1+frac{19}{1}right).left(1+frac{19}{2}right).left(1+frac{19}{3}right).....left(1+frac{19}{17}right)}b) frac{frac{-6}{5}+frac{6}{19}-frac{6}{23}}{frac{9}{5}-frac{9}{19}+frac{9}{23}}c) frac{frac{1}{6}-frac{1}{39}+frac{1}{51}}{frac{1}{8}-frac{1}{52}+frac{1}{68}}d) frac{frac{2}{3}-frac{2}{5}-frac{2}{7}+frac{2}{11}}{frac{13}{3}-frac{13}{5}-frac{13}{7}+frac{13}{11}}e) frac{fra...
Đọc tiếp
1) Tính:
a) \(\frac{\left(1+\frac{17}{1}\right).\left(1+\frac{17}{2}\right).\left(1+\frac{17}{3}\right).....\left(1+\frac{17}{19}\right)}{\left(1+\frac{19}{1}\right).\left(1+\frac{19}{2}\right).\left(1+\frac{19}{3}\right).....\left(1+\frac{19}{17}\right)}\)
b) \(\frac{\frac{-6}{5}+\frac{6}{19}-\frac{6}{23}}{\frac{9}{5}-\frac{9}{19}+\frac{9}{23}}\)
c) \(\frac{\frac{1}{6}-\frac{1}{39}+\frac{1}{51}}{\frac{1}{8}-\frac{1}{52}+\frac{1}{68}}\)
d) \(\frac{\frac{2}{3}-\frac{2}{5}-\frac{2}{7}+\frac{2}{11}}{\frac{13}{3}-\frac{13}{5}-\frac{13}{7}+\frac{13}{11}}\)
e) \(\frac{\frac{1}{1009}+\frac{1}{1010}+\frac{1}{1011}+...+\frac{1}{2017}}{1-\frac{1}{2}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{2015}-\frac{1}{2016}+\frac{1}{2017}}\)
2) CMR: \(\frac{1}{2^2}+\frac{1}{2^4}+\frac{1}{2^6}+...+\frac{1}{2^{800}}< \frac{1}{3}\)
a) \(\frac{8^{15}.3^{16}}{4^{23}.9^8}\)
b) \(\sqrt{121}-4.\sqrt{9}+\sqrt{36}\)
c) \(\frac{2^2}{5^2}+5\frac{1}{2}.\left(4,5-2,5\right)+\frac{2^3}{-4}+\left(-2016\right)^0\)