\(C=\frac{1}{1+\frac{2}{3-\frac{4}{5-7}}}=\frac{1}{1+\frac{2}{3-\left(-2\right)}}=\frac{1}{1+\frac{2}{5}}=\frac{1}{\frac{7}{5}}=\frac{5}{7}\)
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tính :
a) \(\frac{4}{9}:\frac{-1}{7}+6\frac{5}{9}:\frac{-1}{7}\)
b) \(\left(2\frac{1}{3}+3\frac{1}{2}\right):\left(-4\frac{1}{6}+3\frac{1}{7}\right)+7\frac{1}{2}\)
c) \(\frac{\left(13\frac{1}{4}-2\frac{5}{27}-10\frac{5}{6}\right).230\frac{1}{25}+46\frac{3}{4}}{\left(1\frac{3}{7}+\frac{10}{3}\right):\left(12\frac{1}{3}-14\frac{2}{7}\right)}\)
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= \(\frac{1}{100}-\frac{1}{100.99}-\frac{1}{99.98}-...-\frac{1}{3.2}-\frac{1}{2.1}\)
Tính : A left(1-frac{2}{3}+frac{4}{3}right)-left(frac{4}{5}-1right)+left(frac{7}{5}+2right)B left(-3+frac{3}{4}-frac{1}{3}right):left(5+frac{2}{5}-frac{2}{3}right)C left(frac{3}{5}-frac{4}{5}right).left(frac{2}{7}-frac{3}{14}right)-left(frac{5}{9}-frac{7}{27}right).left(1-frac{3}{5}right)+left(1-frac{11}{12}right).left(1-frac{11}{12}right)
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Tính :
A = \(\left(1-\frac{2}{3}+\frac{4}{3}\right)-\left(\frac{4}{5}-1\right)+\left(\frac{7}{5}+2\right)\)
B = \(\left(-3+\frac{3}{4}-\frac{1}{3}\right):\left(5+\frac{2}{5}-\frac{2}{3}\right)\)
C = \(\left(\frac{3}{5}-\frac{4}{5}\right).\left(\frac{2}{7}-\frac{3}{14}\right)-\left(\frac{5}{9}-\frac{7}{27}\right).\left(1-\frac{3}{5}\right)+\left(1-\frac{11}{12}\right).\left(1-\frac{11}{12}\right)\)
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
\(\frac{17}{9}-\frac{17}{9}:\left(\frac{7}{3}+\frac{1}{2}\right)\)
\(\frac{4}{3}.\frac{2}{5}-\frac{3}{4}.\frac{2}{5}\)
\(-\frac{3}{4}.5\frac{3}{13}-0.75.\frac{36}{13}\)
\(3.\left(-\frac{4}{3}\right)^2-\frac{7}{3}\)
\(-\frac{5}{7}.\frac{3}{11}+\frac{-5}{7}.\frac{8}{11}+3\frac{5}{7}\)
\(32\frac{1}{7}:\left(\frac{-5}{4}\right)-47\frac{1}{7}:\left(\frac{-5}{4}\right)\)
\(\left(\frac{2}{3}+\frac{1}{2}\right)^2-\frac{1}{12}\\ \frac{1}{4}-\frac{5}{12}:\frac{1}{6}+\frac{-6}{5}\\ \frac{17}{21}+\frac{5}{23}-\frac{1}{2}+\frac{4}{21}-1\frac{5}{23}\)
\(\left(-3\right)^2+\sqrt{\frac{16}{25}}-\sqrt{9}+\frac{\sqrt{81}}{3}\)
Tính :
\(B=\frac{7}{4}\left(\frac{33}{12}+\frac{3333}{2020}+\frac{333333}{303030}+\frac{33333333}{42424242}\right)\)
\(C=\frac{\left(13\frac{1}{4}-2\frac{5}{27}-10\frac{5}{6}\right).230\frac{1}{25}+46\frac{3}{4}}{\left(1\frac{3}{7}+\frac{10}{3}\right):\left(12\frac{1}{3}-14\frac{2}{7}\right)}\)
1) Tính bằng cách hợp lí nếu có thể:
a) \(1\frac{4}{23}+\frac{5}{21}-\frac{4}{23}+0,5+\frac{16}{21}\)
b) \(\frac{3}{7}.19\frac{1}{3}-\frac{3}{7}.33\frac{1}{3}\)
c) \(9.\left(-\frac{1}{3}\right)^3+\frac{1}{3}\)
d) \(15\frac{1}{4}:\left(-\frac{5}{7}\right)-25\frac{1}{4}:\left(-\frac{5}{7}\right)\)
thực hiện phép tính : ( tính nhanh nếu có thể )a) left(frac{11}{12}:frac{33}{16}right).frac{3}{5}+frac{7}{23}.left[left(frac{-8}{6}+frac{-45}{18}right)right]b) left(frac{-2}{3}+frac{3}{7}right):frac{4}{5}+left(frac{-1}{3}+frac{4}{7}right):frac{4}{5}c) frac{5}{9}:left(frac{1}{11}-frac{5}{22}right)+frac{5}{9}:left(frac{1}{15}-frac{2}{3}right)d) frac{-3}{4}.frac{12}{-5}.frac{-25}{6}+left(-2right).frac{-38}{21}.frac{-7}{4}.frac{-3}{8}
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thực hiện phép tính : ( tính nhanh nếu có thể )
a) \(\left(\frac{11}{12}:\frac{33}{16}\right).\frac{3}{5}+\frac{7}{23}.\left[\left(\frac{-8}{6}+\frac{-45}{18}\right)\right]\)
b) \(\left(\frac{-2}{3}+\frac{3}{7}\right):\frac{4}{5}+\left(\frac{-1}{3}+\frac{4}{7}\right):\frac{4}{5}\)
c) \(\frac{5}{9}:\left(\frac{1}{11}-\frac{5}{22}\right)+\frac{5}{9}:\left(\frac{1}{15}-\frac{2}{3}\right)\)
d) \(\frac{-3}{4}.\frac{12}{-5}.\frac{-25}{6}+\left(-2\right).\frac{-38}{21}.\frac{-7}{4}.\frac{-3}{8}\)
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 = \(1-\frac{1}{3}-\frac{1}{6}-\frac{1}{10}-\frac{1}{15}-...-\frac{1}{1225}\)
Thực hiện phép tính:a) frac{11}{24}-frac{5}{41}+frac{13}{24}+0,5-frac{36}{41}b)-12:left(frac{3}{4}-frac{5}{6}right)^2c)frac{7}{23}.left[left(frac{-8}{6}right)-frac{45}{18}right]d)23frac{1}{4}.frac{7}{5}-13frac{1}{4}:frac{5}{7}e)left(1+frac{2}{3}-frac{1}{4}right).left(0,8-frac{3}{4}right)^2
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Thực hiện phép tính:
a) \(\frac{11}{24}-\frac{5}{41}+\frac{13}{24}+0,5-\frac{36}{41}\)
b)\(-12:\left(\frac{3}{4}-\frac{5}{6}\right)^2\)
c)\(\frac{7}{23}.\left[\left(\frac{-8}{6}\right)-\frac{45}{18}\right]\)
d)\(23\frac{1}{4}.\frac{7}{5}-13\frac{1}{4}:\frac{5}{7}\)
e)\(\left(1+\frac{2}{3}-\frac{1}{4}\right).\left(0,8-\frac{3}{4}\right)^2\)
Thực hiện phép tínha)16frac{2}{7}:left(frac{-3}{5}right)+28frac{2}{7}:frac{3}{5}b)left(2^2:frac{4}{3}-frac{1}{2}right).frac{6}{5}-17c)left(frac{1}{3}right)^{50}.left(-9right)^{25}-frac{2}{3}:4d)frac{3}{5}:left(frac{-1}{15}-frac{1}{6}right)+frac{3}{5}:left(frac{-1}{3}-1frac{1}{15}right)e)left(-6,5right).5,7+5,7.left(-3,5right)
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Thực hiện phép tính
a)\(16\frac{2}{7}:\left(\frac{-3}{5}\right)+28\frac{2}{7}:\frac{3}{5}\)
b)\(\left(2^2:\frac{4}{3}-\frac{1}{2}\right).\frac{6}{5}-17\)
c)\(\left(\frac{1}{3}\right)^{50}.\left(-9\right)^{25}-\frac{2}{3}:4\)
d)\(\frac{3}{5}:\left(\frac{-1}{15}-\frac{1}{6}\right)+\frac{3}{5}:\left(\frac{-1}{3}-1\frac{1}{15}\right)\)
e)\(\left(-6,5\right).5,7+5,7.\left(-3,5\right)\)