Các câu hỏi tương tự
Tìm tích:
1.\(\left(\frac{1}{2}+1\right)\times\left(\frac{1}{3}+1\right)\times\left(\frac{1}{4}+1\right)\times...\times\left(\frac{1}{999}+1\right)\)
2.\(\left(\frac{1}{2}-1\right)\times\left(\frac{1}{3}-1\right)\times\left(\frac{1}{4}-1\right)\times...\times\left(\frac{1}{1000}-1\right)\)
3.\(\frac{3}{2^2}\times\frac{8}{3^2}\times\frac{15}{4^2}\times...\times\frac{99}{10^2}\)
tính giá trị biểu thứca, Afrac{-1}{2}-left[frac{-3}{5}right]+left[frac{-1}{9}right]+frac{1}{27}+frac{7}{18}+frac{4}{35}-left[-frac{2}{7}right]b, Bfrac{1}{3}-frac{3}{4}-left[frac{-3}{5}-frac{1}{57}+frac{1}{36}+frac{-1}{15}right]-frac{2}{9}c, Cleft[-frac{7}{15}right]timesfrac{5}{8}timesleft[frac{30}{-7}right]timesleft[-16right]timesleft[frac{-1}{1000}right]d, Dfrac{1}{2}timesfrac{-11}{19}-50%timesleft[-frac{1}{19}right]+frac{10}{19}timesfrac{1111}{2222}
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tính giá trị biểu thức
a, A=\(\frac{-1}{2}-\left[\frac{-3}{5}\right]+\left[\frac{-1}{9}\right]+\frac{1}{27}+\frac{7}{18}+\frac{4}{35}-\left[-\frac{2}{7}\right]\)
b, B=\(\frac{1}{3}-\frac{3}{4}-\left[\frac{-3}{5}-\frac{1}{57}+\frac{1}{36}+\frac{-1}{15}\right]-\frac{2}{9}\)
c, C=\(\left[-\frac{7}{15}\right]\times\frac{5}{8}\times\left[\frac{30}{-7}\right]\times\left[-16\right]\times\left[\frac{-1}{1000}\right]\)
d, D=\(\frac{1}{2}\times\frac{-11}{19}-50\%\times\left[-\frac{1}{19}\right]+\frac{10}{19}\times\frac{1111}{2222}\)
1) Rút gọn biểu thức M:
\(\frac{\frac{2}{5}+\frac{2}{7}-\frac{2}{9}-\frac{2}{11}}{\frac{4}{5}+\frac{4}{7}-\frac{4}{9}-\frac{2}{11}}\)
2) Tính nhanh:
\(A=\left(1-\frac{1}{2}\right)\times\left(1-\frac{1}{3}\right)\times\left(1-\frac{1}{4}\right)\times\left(1-\frac{1}{5}\right)\times....\times\left(1-\frac{1}{100}\right)\)
\(\left(1-\frac{1}{2^2}\right)\times\left(1-\frac{1}{3^2}\right)\times\left(1-\frac{1}{4^2}\right)\times...\times\left(1-\frac{1}{10^2}\right)\)
D=\(\left(\frac{1}{2^2}-1\right)\times\left(\frac{1}{3^2}-1\right)\times\left(\frac{1}{4^2}-1\right)\times...\times\left(\frac{1}{100^2}-1\right)\)
1. Tính :
a.\(\frac{\frac{2}{7}+\frac{2}{5}+\frac{2}{17}+\frac{2}{293}}{\frac{3}{7}+\frac{3}{5}+\frac{3}{17}+\frac{3}{293}}+\frac{\frac{7}{12}+\frac{5}{6}-1}{5-\frac{3}{4}+\frac{1}{3}}\)
b.\(\left(1-\frac{1}{7}\right)\times\left(1-\frac{2}{7}\right)\times\left(1-\frac{3}{7}\right)\times......\times\left(1-\frac{10}{7}\right)\)
BÀI 1:TÍNHAfrac{7^2}{7times8}timesfrac{8^2}{8times9}times...timesfrac{11^2}{11times12}Bleft(1+frac{1}{11}right)timesleft(1+frac{1}{12}right)times...timesleft(1+frac{1}{15}right)Cleft(1-frac{1}{2}right)timesleft(1-frac{1}{3}right)timesleft(1-frac{1}{4}right)times...timesleft(1-frac{1}{2010}right)Dleft(frac{1}{2}-1right)timesleft(frac{1}{3}-1right)timesleft(frac{1}{4}-1right)times...timesleft(frac{1}{2010}-1right)BÀI 2: Tìm phân số tối giản frac{a}{b}nhỏ nhất (a,b thuộc N sao)để khi nhân frac{a}{b...
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BÀI 1:TÍNH
A=\(\frac{7^2}{7\times8}\times\frac{8^2}{8\times9}\times...\times\frac{11^2}{11\times12}\)
B=\(\left(1+\frac{1}{11}\right)\times\left(1+\frac{1}{12}\right)\times...\times\left(1+\frac{1}{15}\right)\)
C=\(\left(1-\frac{1}{2}\right)\times\left(1-\frac{1}{3}\right)\times\left(1-\frac{1}{4}\right)\times...\times\left(1-\frac{1}{2010}\right)\)
D=\(\left(\frac{1}{2}-1\right)\times\left(\frac{1}{3}-1\right)\times\left(\frac{1}{4}-1\right)\times...\times\left(\frac{1}{2010}-1\right)\)
BÀI 2: Tìm phân số tối giản \(\frac{a}{b}\)nhỏ nhất (a,b thuộc N sao)để khi nhân \(\frac{a}{b}với\frac{55}{16}:\frac{25}{24}\)được tích là các số tự nhiên.
E=\(1+\frac{1}{2}\times\left(1+2\right)+\frac{1}{3}\times\left(1+2+3\right)\frac{1}{4}\times\left(1+2+3+\right)+....+\frac{1}{200}\times\left(1+2+3+....+2001\right)\)
tính các tích sauafrac{3}{4}timesfrac{8}{9}timesfrac{15}{16}times...timesfrac{9999}{10000}bleft(1-frac{1}{4}right)timesleft(1-frac{1}{9}right)times...timesleft(1-frac{1}{10000}right)cleft(1-frac{1}{2}right)timesleft(1-frac{1}{3}right)times...timesleft(1-frac{1}{1994}right)dleft(1+frac{1}{1times3}right)timesleft(1+frac{1}{2times4}right)timesleft(1+frac{1}{3times5}right)times...timesleft(1+frac{1}{99times100}right)
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tính các tích sau
\(a=\frac{3}{4}\times\frac{8}{9}\times\frac{15}{16}\times...\times\frac{9999}{10000}\)
\(b=\left(1-\frac{1}{4}\right)\times\left(1-\frac{1}{9}\right)\times...\times\left(1-\frac{1}{10000}\right)\)
\(c=\left(1-\frac{1}{2}\right)\times\left(1-\frac{1}{3}\right)\times...\times\left(1-\frac{1}{1994}\right)\)
\(d=\left(1+\frac{1}{1\times3}\right)\times\left(1+\frac{1}{2\times4}\right)\times\left(1+\frac{1}{3\times5}\right)\times...\times\left(1+\frac{1}{99\times100}\right)\)