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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=\(\frac{3}{1.4}+\frac{5}{4.9}+\frac{7}{9.16}+\frac{9}{16.25}+\frac{11}{25.36}\)
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...
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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: \(\frac{1}{2^2}+\frac{1}{2^4}+\frac{1}{2^6}+...+\frac{1}{2^{800}}< \frac{1}{3}\)
2/6+9/20-11/30+13/42-15/56+17/72-19/90+21/110-23/132
ai giúp mình cách giải với mai mình phải nộp rồi
please help meee
2 Thực hiện phép tínhfrac{17}{9}-frac{17}{9}:left(frac{7}{3}+frac{1}{2}right)frac{4}{3}.frac{2}{5}-frac{3}{4}.frac{2}{5}-frac{3}{4}.5frac{3}{13}-0.75.frac{36}{13}3.left(-frac{4}{3}right)^2-frac{7}{3}-frac{5}{7}.frac{3}{11}+frac{-5}{7}.frac{8}{11}+3frac{5}{7}32frac{1}{7}:left(frac{-5}{4}right)-47frac{1}{7}:left(frac{-5}{4}right)left(frac{2}{3}+frac{1}{2}right)^2-frac{1}{12} frac{1}{4}-frac{5}{12}:frac{1}{6}+frac{-6}{5} frac{17}{21}+frac{5}{23}-frac{1}{2}+frac{4}{21}-1frac{5}{23}left(-3right)^2+sq...
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2 Thực hiện phép tính
\(\frac{17}{9}-\frac{17}{9}:\left(\frac{7}{3}+\frac{1}{2}\right)\)
\(\frac{4}{3}.\frac{2}{5}-\frac{3}{4}.\frac{2}{5}\)
\(-\frac{3}{4}.5\frac{3}{13}-0.75.\frac{36}{13}\)
\(3.\left(-\frac{4}{3}\right)^2-\frac{7}{3}\)
\(-\frac{5}{7}.\frac{3}{11}+\frac{-5}{7}.\frac{8}{11}+3\frac{5}{7}\)
\(32\frac{1}{7}:\left(\frac{-5}{4}\right)-47\frac{1}{7}:\left(\frac{-5}{4}\right)\)
\(\left(\frac{2}{3}+\frac{1}{2}\right)^2-\frac{1}{12}\\ \frac{1}{4}-\frac{5}{12}:\frac{1}{6}+\frac{-6}{5}\\ \frac{17}{21}+\frac{5}{23}-\frac{1}{2}+\frac{4}{21}-1\frac{5}{23}\)
\(\left(-3\right)^2+\sqrt{\frac{16}{25}}-\sqrt{9}+\frac{\sqrt{81}}{3}\)
24 tháng 9 2016 lúc 9:59
a) \(\left(-\frac{40}{51}\cdot0,32\cdot\frac{17}{20}\right):\frac{64}{75}\)
b) \(-\frac{10}{11}\cdot\frac{8}{9}+\frac{7}{18}\cdot\frac{10}{11}\)
c) \(\frac{3}{14}:\frac{1}{28}-\frac{13}{21}:\frac{11}{28}+\frac{29}{42}:\frac{1}{28}-8\)
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 = \(1-\frac{1}{3}-\frac{1}{6}-\frac{1}{10}-\frac{1}{15}-...-\frac{1}{1225}\)
Giúp mik nkaBài 1: Tính giá trị của biểu thức ( hợp lí nếu có thể)a/ |-10| : (-2): (-5)+(-3)2b/ 1+ (-2) +3 +(-4) + 5+ (-6)+....+ 21 (-22)c/ frac{3}{4}.frac{5}{9}+frac{3}{4}.frac{4}{9}d/ frac{-4}{17}+frac{5}{19}+frac{-13}{17}+frac{14}{19}+frac{3}{115}e/ left(frac{3}{4}+frac{-7}{2}right).left(frac{10}{11}+frac{2}{22}right)Thanks. Nhanh hộ mik
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Giúp mik nka
Bài 1: Tính giá trị của biểu thức ( hợp lí nếu có thể)
a/ |-10| : (-2): (-5)+(-3)2
b/ 1+ (-2) +3 +(-4) + 5+ (-6)+....+ 21 (-22)
c/ \(\frac{3}{4}.\frac{5}{9}+\frac{3}{4}.\frac{4}{9}\)
d/ \(\frac{-4}{17}+\frac{5}{19}+\frac{-13}{17}+\frac{14}{19}+\frac{3}{115}\)
e/ \(\left(\frac{3}{4}+\frac{-7}{2}\right).\left(\frac{10}{11}+\frac{2}{22}\right)\)
Thanks. Nhanh hộ mik
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= \(\frac{1}{100}-\frac{1}{100.99}-\frac{1}{99.98}-...-\frac{1}{3.2}-\frac{1}{2.1}\)
bài 1 ; thực hiện phép tính (tính nhanh nếu có thể)
a) \(\left(\frac{-1}{4}+\frac{7}{33}-\frac{5}{3}\right)-\left(\frac{-15}{12}+\frac{6}{11}-\frac{48}{49}\right)\)
b) \(\frac{3}{14}:\frac{1}{28}-\frac{13}{21}:\frac{1}{28}+\frac{29}{42}:\frac{1}{28}-8\)