= -1/3-3/7.(3/9+1)
= -1/3-3/7.4/3
=1/3-4/7
= -5/21
= -1/3-3/7.(3/9+1)
= -1/3-3/7.4/3
=1/3-4/7
= -5/21
1. Tính tổng
\(\frac{1}{2}\cdot\frac{1}{3}\cdot+\frac{1}{3}\cdot\frac{1}{4}+\frac{1}{4}\cdot\frac{1}{5}+\frac{1}{5}\cdot\frac{1}{6}+\frac{1}{6}\cdot\frac{1}{7}+\frac{1}{7}\cdot\frac{1}{8}+\frac{1}{8}\cdot\frac{1}{9}\)
tinh hop li :
\(\frac{\left(\frac{1}{5}-\frac{2}{7}\right)\cdot\frac{3}{4}-\frac{3}{4}\cdot\left(\frac{1}{3}-\frac{2}{7}\right)}{\frac{1}{5}\cdot\frac{2}{7}-\frac{1}{3}\cdot\left(\frac{2}{7}+\frac{3}{9}\right)+\frac{3}{9}+\frac{1}{5}}\)
cham la nhan nha cac ban
ai nhanh mk tick cho
tính:
A=\(\frac{1^2}{1\cdot2}\cdot\frac{2^2}{2\cdot3}\cdot\frac{3^2}{3\cdot4}\cdot\frac{4^2}{4\cdot5}...\frac{8^2}{8\cdot9}\cdot\frac{9^2}{9\cdot10}\)
B=\(\frac{2^2}{3}\cdot\frac{^{3^2}}{8}\cdot\frac{4^2}{15}\cdot\frac{6^2}{35}\cdot\frac{7^2}{48}\cdot\frac{8^2}{63}\cdot\frac{9^2}{80}\)
tính nhanh P =\(\frac{6}{7}\)*\(\frac{8}{13}+\frac{6}{9}\cdot\frac{9}{7}-\frac{3}{13}\cdot\frac{6}{7}\)
cách giải
Tính giá trị biểu thức
a,\(A=\frac{24\cdot47-23}{24+47-23}\cdot\frac{3+\frac{3}{7}-\frac{3}{11}+\frac{3}{1001}-\frac{3}{13}}{\frac{9}{1001}-\frac{9}{13}+\frac{9}{7}-\frac{9}{11}+9}\)
b,\(M=\frac{1+2+2^2+2^3+...+2^{2012}}{2^{2014}-2}\)
c,\(A=81\cdot\left[\frac{12-\frac{12}{7}-\frac{12}{289}-\frac{12}{85}}{4-\frac{4}{7}-\frac{4}{289}-\frac{4}{85}}:\frac{5+\frac{5}{13}+\frac{5}{169}+\frac{5}{91}}{6+\frac{6}{13}+\frac{6}{169}+\frac{6}{91}}\right]:\frac{158158158}{711711711}\)
d,\(A=\frac{5\cdot\left(2^2.3^2\right)^9\cdot\left(2^2\right)^6-2\cdot\left(2^2\cdot3\right)^{14}\cdot3^4}{5\cdot2^{28}\cdot3^{18}-7\cdot2^{29}\cdot3^{18}}\)
Tính nhanh :
A= \(\frac{24\cdot43-23}{24+47-23}\cdot\frac{3+\frac{3}{7}-\frac{3}{11}+\frac{3}{1001}-\frac{3}{13}}{\frac{9}{1001}-\frac{9}{13}+\frac{9}{7}-\frac{9}{11}+9}\)
Giải hộ đúng mk tick
Tính giá trị biểu thức(giút gọn biểu thức)
A=\(\left(\left(\frac{2}{193}-\frac{3}{386}\right)\cdot\frac{193}{17}+\frac{33}{34}\right):\left(\left(\frac{7}{2001}+\frac{11}{4002}\right)\cdot\frac{2001}{25}+\frac{9}{2}\right)\)
\(B=\left(1+2+3+4+.....+100\right)\cdot\left(\frac{1}{3}-\frac{1}{5}+\frac{1}{7}-\frac{1}{9}\right)\cdot\left(\frac{6}{3}\cdot12-2,1\cdot3,6\right)\)
C=\(\frac{2\cdot8^4\cdot27^2+4\cdot69}{2^7\cdot6^7+2^7\cdot40\cdot9^4}\)
\(F=1-\frac{1}{1+\frac{2}{1-\frac{3}{1-4}}}\)
ai làm đúng nhanh dễ hiểu thì mk tick cho
tính nhanh
\(\frac{19}{37}+\left(1-\frac{19}{37}\right)\)
\(\frac{7}{13}\cdot\frac{5}{14}\cdot\frac{39}{15}\)
\(2\frac{3}{7}\cdot\frac{1}{2}-\frac{1}{2}\cdot\frac{3}{7}+\frac{1}{3}\)
\(\frac{9}{5}:\frac{17}{15}+\frac{8}{5}:\frac{17}{15}\)
\(\frac{2017}{2018}\cdot\frac{1}{2019}+\frac{2017}{2018}:\frac{2019}{2018}+\frac{1}{2018}\)
\(\frac{637\cdot527-189}{526\cdot637+448}\)
\(\frac{4}{5\cdot7}+\frac{4}{7\cdot9}+\frac{4}{9\cdot11}+...+\frac{4}{23\cdot25}\)
dấu . là dấu nhân nha mọi người
tính nhanh
A= \(\frac{19}{23}\cdot\frac{-4}{7}-\frac{4}{23}\cdot\frac{2}{7}\)
B= \(\frac{3}{5}+\frac{2}{5}\cdot\frac{-11}{3}+\frac{2}{3}\cdot\frac{-2}{5}+\frac{14}{15}\)