tinh hop li neu co the \(\frac{3}{4}.\frac{2}{5}-\frac{3}{10}.\frac{4}{3}\)
Những câu hỏi liên quan
\(\frac{-7}{25}+0,25.\frac{10}{19}+\frac{1}{4}.\frac{9}{19}+\frac{18}{25}\)
Tinh hop ly neu co the
\(-\frac{7}{25}+0,25.\frac{10}{19}+\frac{1}{4}.\frac{9}{19}+\frac{18}{25}\)
\(=\frac{-7+18}{25}+\frac{1}{4}.\frac{10}{19}+\frac{1}{4}.\frac{9}{19}\)
\(=\frac{11}{25}+\frac{19}{4.19}\)
\(=\frac{11}{25}+\frac{1}{4}\)
\(=\frac{69}{100}\)
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\(s=\frac{1}{2}-\frac{2}{3}+\frac{3}{4}-\frac{4}{5}+\frac{5}{6}+\frac{4}{5}-\frac{3}{4}+\frac{2}{3}-\frac{1}{2}\)
tinh hop li
\(S=\frac{1}{2}-\frac{2}{3}+\frac{3}{4}-\frac{4}{5}+\frac{5}{6}+\frac{4}{5}-\frac{3}{4}+\frac{2}{3}-\frac{1}{2}\)
\(S=\left(\frac{1}{2}-\frac{1}{2}\right)-\left(\frac{2}{3}-\frac{2}{3}\right)+\left(\frac{3}{4}-\frac{3}{4}\right)-\left(\frac{4}{5}-\frac{4}{5}\right)+\frac{5}{6}\)
\(S=0-0+0-0+\frac{5}{6}\)
\(S=0+\frac{5}{6}\)
\(S=\frac{5}{6}\)
Cẩn thận nha mấy bn, bài này dễ sai dấu lém đó ng kq vẫn đúng
Ủng hộ mk nha ^_^
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\(S=\frac{1}{2}-\frac{2}{3}+\frac{3}{4}-\frac{4}{5}+\frac{5}{6}+\frac{4}{5}-\frac{3}{4}+\frac{2}{3}-\frac{1}{2}\)
\(\Rightarrow S=\left(\frac{1}{2}-\frac{1}{2}\right)+\left(\frac{3}{4}-\frac{3}{4}\right)-\left(\frac{4}{5}-\frac{4}{5}\right)-\left(\frac{2}{3}-\frac{2}{3}\right)+\frac{5}{6}\)
\(\Rightarrow S=\frac{5}{6}\)
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\(\frac{\frac{1}{3}-\frac{1}{7}-\frac{1}{13}}{\frac{2}{3}-\frac{2}{7}-\frac{2}{13}}.\frac{\frac{3}{4}-\frac{3}{16}-\frac{3}{64}-\frac{3}{264}}{1-\frac{1}{4}-\frac{1}{16}-\frac{1}{64}}+\frac{5}{8}\)
tinh nhanh neu co the
\(\frac{\frac{1}{3}-\frac{1}{7}-\frac{1}{13}}{\frac{2}{3}-\frac{2}{7}-\frac{2}{13}}\cdot\frac{\frac{3}{4}-\frac{3}{16}-\frac{3}{64}-\frac{3}{264}}{1-\frac{1}{4}-\frac{1}{16}-\frac{1}{64}}+\frac{5}{8}\)
\(=\frac{\frac{1}{3}-\frac{1}{7}-\frac{1}{13}}{2\left(\frac{1}{3}-\frac{1}{7}-\frac{1}{13}\right)}\cdot\frac{\frac{3}{4}\left(1-\frac{1}{4}-\frac{1}{16}-\frac{1}{64}\right)}{1-\frac{1}{4}-\frac{1}{16}-\frac{1}{64}}\)\(+\frac{5}{8}\)
\(\frac{1}{2}\cdot\frac{3}{4}+\frac{5}{8}=\frac{3}{8}+\frac{5}{8}=1\)
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Tinh bang cach hop li
c)\(\frac{-5}{7}+\frac{3}{4}+\frac{-1}{5}+\) \(\frac{-2}{7}+\frac{1}{4}\)
bằng-1/5
\(\frac{-5}{7}+\frac{3}{4}+\frac{-1}{5}+\frac{-2}{7}+\frac{1}{4}\)
\(=\left(\frac{-5}{7}+\frac{-2}{7}\right)+\left(\frac{3}{4}+\frac{1}{4}\right)+\frac{-1}{5}\)
\(=-1+1+\frac{-1}{5}\)
\(=-\frac{1}{5}\)
tinh hop li :
\(\frac{\left(\frac{1}{5}-\frac{2}{7}\right)\cdot\frac{3}{4}-\frac{3}{4}\cdot\left(\frac{1}{3}-\frac{2}{7}\right)}{\frac{1}{5}\cdot\frac{2}{7}-\frac{1}{3}\cdot\left(\frac{2}{7}+\frac{3}{9}\right)+\frac{3}{9}+\frac{1}{5}}\)
Tinh bang cach hop li
c) \(\frac{-5}{7}+\frac{3}{4}+\frac{-1}{5}\) \(+\frac{-2}{7}+\frac{1}{4}\)
=(-5/7-2/7)+(3/4+1/4)-1/5=-1+1-1/5=-1/5
(-5/7+-2/7)+(3/4+1/4)+-1/5
-1+1+-1/5
-1/5
c, \(\frac{-5}{7}+\frac{3}{4}+\frac{-1}{5}+\frac{-2}{7}+\frac{1}{4}\)
\(=\left(-\frac{5}{7}-\frac{2}{7}\right)+\left(\frac{3}{4}+\frac{1}{4}\right)-\frac{1}{5}\)
\(=-1+1-\frac{1}{5}=-\frac{1}{5}\)
Tinh (tinh nhanh neu co the)
\(2-\frac{2}{3+\frac{1}{2}}\) va \(\frac{1-\frac{1}{\frac{3}{4}+1}}{3}\)
\(2-\frac{2}{3+\frac{1}{2}}=2-\frac{2}{\frac{6}{2}+\frac{1}{2}}=2-\frac{2}{\frac{7}{2}}=2-2:\frac{7}{2}=2-\frac{4}{7}=\frac{10}{7}\)
\(\frac{1-\frac{1}{\frac{3}{4}+1}}{3}=1-\frac{1}{\frac{7}{\frac{4}{3}}}=1-\frac{1}{7}:\frac{4}{3}=1-\frac{3}{28}=\frac{25}{28}\)
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Tinh bang cach hop ly
Xem chi tiết
a, \(\frac{\frac{7}{12}+\frac{5}{6}-1}{5-\frac{3}{4}+\frac{1}{3}}\)
khong quy dong tinh hop li
B\(=\frac{5}{2\times1}+\frac{4}{1\times11}+\frac{3}{11\times2}+\frac{1}{2\times15}+\frac{13}{15\times4}\)
1/7B=5/2.7+4/7.11+3/11.14+1/14.15+13/15.28
1/7B=1/2-1/7+1/7-1/11+1/11-1/14+1/14-1/15+1/15-1/28
1/7B=1/2-1/28
B=(1/2-1/28):1/7
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