\(\frac{1}{10}\times\frac{2}{10}-\frac{1}{10}=\)
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Những câu hỏi liên quan
Aleft(1frac{1}{6}timesfrac{6}{7}times6:frac{3}{5}right):left(4frac{1}{5}timesfrac{10}{11}+5frac{2}{10}right)B1frac{13}{15}times25%times3+left(frac{8}{15}-frac{79}{60}right):1frac{23}{4}Cfrac{123}{4567}timesfrac{1}{8}+frac{123}{4567}timesfrac{1}{2}-frac{123}{4567}timesfrac{13}{8}Dfrac{10frac{1}{3}timesleft(24frac{1}{2}-15frac{6}{7}right)-frac{12}{11}timesleft(frac{10}{3}-1,75right)}{left(frac{5}{9}-0,25right)timesfrac{60}{11}+194frac{8}{99}}
Đọc tiếp
\(A=\left(1\frac{1}{6}\times\frac{6}{7}\times6:\frac{3}{5}\right):\left(4\frac{1}{5}\times\frac{10}{11}+5\frac{2}{10}\right)\)
\(B=1\frac{13}{15}\times25\%\times3+\left(\frac{8}{15}-\frac{79}{60}\right):1\frac{23}{4}\)
\(C=\frac{123}{4567}\times\frac{1}{8}+\frac{123}{4567}\times\frac{1}{2}-\frac{123}{4567}\times\frac{13}{8}\)
\(D=\frac{10\frac{1}{3}\times\left(24\frac{1}{2}-15\frac{6}{7}\right)-\frac{12}{11}\times\left(\frac{10}{3}-1,75\right)}{\left(\frac{5}{9}-0,25\right)\times\frac{60}{11}+194\frac{8}{99}}\)
tính bằng cách thuận tiện
a. \(\frac{1}{2}\times\frac{2}{3}\div\frac{4}{3}\times\frac{4}{5}\div\frac{6}{5}\times\frac{6}{7}\div\frac{7}{8}\times\frac{8}{9}\div\frac{10}{9}\)
b.\(\frac{27}{49}\times\frac{49}{50}\times\frac{15}{51}\times(\frac{5}{10}-\frac{1}{2})\)
(7x6=5+2+6x7) =
\(\frac{1}{15}< \frac{1}{2}\times\frac{3}{4}\times...\times\frac{99}{100}< \frac{1}{10}\)
Tìm x biết :
\(\frac{10}{1\times2}+\frac{10}{2\times3}+...+\frac{10}{x\times\left(x+1\right)}=9\)
\(\Leftrightarrow10\times\left(\frac{1}{1\times2}+\frac{1}{2\times3}+...+\frac{1}{x\times\left(x+1\right)}\right)=9\)
\(\Leftrightarrow\left(\frac{1}{1}-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{x}-\frac{1}{x+1}\right)=9\div10\)
\(\Leftrightarrow\frac{1}{1}-\frac{1}{x+1}=\frac{9}{10}\)
\(\Leftrightarrow\frac{1}{x+1}=1-\frac{9}{10}\)
\(\Leftrightarrow\frac{1}{x+1}=\frac{1}{10}\)
\(\Rightarrow x+1=10\)
\(\Leftrightarrow x=9\)
Vậy x = 9
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\(\left(1-\frac{1}{2^2}\right)\times\left(1-\frac{1}{3^2}\right)\times\left(1-\frac{1}{4^2}\right)\times...\times\left(1-\frac{1}{10^2}\right)\)
Ta có (1-1/2).(1-1/3^2).(1-1/4^2).....(1-1/10^2)
=(2^2-1/2^2).(3^2-1/3^2).....(10^2-1/10)
=(1.3/2^2).(2.4/3^2).....(9.11/10^2)
=11/20
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\(\frac{1}{4}\times\frac{2}{6}\times\frac{3}{8}\times\frac{4}{10}\times\frac{5}{12}.....\frac{30}{62}\times\frac{31}{64}=2^x\)
\(\frac{1}{4}.\frac{2}{6}.\frac{3}{8}.\frac{4}{10}.\frac{5}{12}.....\frac{30}{62}.\frac{31}{64}=2^x\)
=>\(\frac{1}{2.2}.\frac{2}{2.3}.\frac{3}{2.4}.\frac{4}{2.5}.\frac{5}{2.6}....\frac{30}{2.31}.\frac{31}{2.32}=2^x\)
=>\(\frac{1.2.3.4.5....30.31}{2.2.2.3.2.4.2.5.2.6...2.31.2.32}=2^x\)
=>\(\frac{2.3.4.5...30.31}{2^{31}.32.\left(2.3.4.5...31\right)}=2^x\)
=>\(\frac{1}{2^{31}.2^5}=2^x\)
=>\(\frac{1}{2^{36}}=2^x\)
=> x=36
Vậy x=36
Chúc bn học tốt nhé!
\(\frac{6\div\frac{3}{5}-1\frac{1}{6}\times\frac{6}{7}}{4\frac{1}{5}\times\frac{10}{11}+5\frac{2}{11}}\)
\(\frac{6\div\frac{3}{5}-1\frac{1}{6}\times\frac{6}{7}}{4\frac{1}{5}\times\frac{10}{11}+5\frac{2}{11}}=\frac{6\div\frac{3}{5}-\frac{1\times6+1}{6}\times\frac{6}{7}}{\frac{4\times5+1}{5}\times\frac{10}{11}+\frac{5\times11+2}{11}}\)
\(=\frac{6\div\frac{3}{5}-\frac{7}{6}\times\frac{6}{7}}{\frac{21}{5}\times\frac{10}{11}+\frac{57}{11}}=\frac{\left(6\div\frac{3}{5}\right)-\left(\frac{7}{6}\times\frac{6}{7}\right)}{\left(\frac{21}{5}\times\frac{10}{11}\right)+\frac{57}{11}}\)
\(=\frac{10-1}{\frac{42}{11}+\frac{57}{11}}=\frac{9}{\frac{99}{11}}=\frac{9}{9}=1\)
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Tìm x biết : \(\frac{1}{4}\times\frac{2}{6}\times\frac{3}{8}\times\frac{4}{10}\times.......\times\frac{30}{62}\times\frac{31}{64}=2^x\)
\(\frac{1.2.3....31}{2^{30}.\left(2.3....31\right).32}=\frac{1}{2^{31}.32}=\frac{1}{2^{36}}=2^{-36}=2^x\)
Vậy x=-36
Hok tốt
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\(A=5,3:\left(5\frac{5}{28}-2\frac{13}{36}+1\frac{16}{63}\right)\)
\(B=\left(\frac{19}{10}\times\frac{19}{10}+\frac{39}{2}:\frac{13}{3}\right)\times\left(\frac{62}{75}-\frac{12}{75}\right)\)