???????????????????????????????????????????????????????????????????????????^_^
= 1/1 - 1/2 + 1/2 - 1/3 +.. + 1/5 - 1/6
= 1/1 - 1/6
= 5/6
???????????????????????????????????????????????????????????????????????????^_^
= 1/1 - 1/2 + 1/2 - 1/3 +.. + 1/5 - 1/6
= 1/1 - 1/6
= 5/6
\(A=\left(6:\frac{3}{5}-1\frac{1}{6}x\frac{6}{7}\right):\left(4\frac{1}{5}x\frac{10}{11}+5\frac{2}{11}\right)\)\(B=\left(1-\frac{1}{2}\right)x\left(1-\frac{1}{4}\right)x.......x\left(1-\frac{1}{2015}\right)x\left(1-\frac{1}{2016}\right)\)
\(C=5\frac{9}{10}:\frac{3}{2}-\left(2\frac{1}{3}x4\frac{1}{2}-2x2\frac{1}{3}\right):\frac{7}{4}\)
Bài1:Tính giá trị biểu thức sau:
A=\(\left(6:\frac{3}{5}-1\frac{1}{6}x\frac{6}{7}\right):\left(4\frac{1}{5}x\frac{10}{11}+5\frac{2}{11}\right)\)
Bài 2: Tính giá trị biểu thức:
B= \(\left(1-\frac{1}{2}\right)x\left(1-\frac{1}{3}\right)x\left(1-\frac{1}{4}\right)x\left(1-\frac{1}{5}\right)...\left(1-\frac{1}{2003}\right)x\left(1-\frac{1}{2004}\right)\)
ai xong sẽ có tích , phải làm giải từng bước ra nhé!
\(HELP\) \(ME\)\(!\)
1.
\(\frac{3}{4}x\frac{8}{5}:1\frac{1}{6}=\)\(2\frac{1}{3}x1\frac{1}{4}-\frac{7}{5}=\)\(4\frac{2}{3}+1\frac{1}{4}+2\frac{1}{3}+2\frac{3}{7}=\)2.
\(x.\frac{1}{2}=\frac{3}{4}+\frac{1}{5}\)\(x-\frac{1}{5}=\frac{2}{3}.\frac{9}{4}\)\(x.\frac{1}{5}+\frac{2}{3}=\frac{5}{4}\)\(\frac{13}{5}:x-\frac{1}{2}=\frac{4}{5}.\frac{15}{16}\)\(x:\frac{4}{9}+\frac{1}{3}=\frac{2}{5}.1\frac{13}{2}\)Chú ý: Dấu chấm là dấu nhânBài 1 : ( 2 điểm) : Tính giá trị của biểu thức .
a , \(\frac{11}{5}x\frac{3}{2}-3\frac{1}{2}x\frac{3}{5}\)
b , \(\left(\frac{1}{2}-\frac{1}{3}+\frac{1}{4}-\frac{1}{5}\right):\left(\frac{1}{4}-\frac{1}{6}\right)\)
1/ Tìm x :
\(\frac{x\times2+5}{x+5}=\frac{6}{4}\)
2/ Tính nhanh :
a) \(\frac{4}{1\times5}+\frac{4}{5\times9}+\frac{4}{9\times13}+\frac{4}{13\times17}+\frac{4}{17\times21}\)
b) \(\left(1-\frac{1}{2}\right)\times\left(1-\frac{1}{3}\right)\times\left(1-\frac{1}{4}\right)\times.......\times\left(1-\frac{1}{2017}\right)\)
c) \(A=2000-5-5-5-.......-5\)( có 200 số 5 )
a)\(\left(1-\frac{1}{2}\right)x\left(1-\frac{1}{3}\right)x\left(1-\frac{1}{4}\right)x\left(1-\frac{1}{5}\right)x......x\left(1-\frac{1}{18}\right)x\left(1-\frac{1}{19}\right)x\left(1-\frac{1}{20}\right)\)
b)\(1\frac{1}{2}x1\frac{1}{3}x1\frac{1}{4}x1\frac{1}{5}x......x1\frac{1}{2005}x1\frac{1}{2006}x1\frac{1}{2007}\)
tính bằng cách thuận tiện
\(\left(1-\frac{1}{2}\right)x\left(1-\frac{1}{3}\right)x\left(1-\frac{1}{4}\right)x\left(1-\frac{1}{5}\right)x\left(1-\frac{1}{6}\right)\))
giúp mik nhé ai nhanh mik k
Tìm x
a \(\frac{3}{4}+\frac{1}{4}xX=2\)
b X - \(\frac{2}{3}x\frac{9}{4}=2,5-\frac{1}{2}\)
c \(2xX+\frac{1}{3}=\frac{4}{3}\)
d \(X:\frac{2}{3}+0,75=\frac{9}{4}+3\)
e \(\frac{6}{4}:X+\frac{1}{2}=\frac{9}{4}x\frac{2}{3}\)
f \(Xx\frac{3}{5}-\frac{2}{5}=3\frac{3}{4}-1\)
Tính nhanh
a)\(\frac{11}{15}+\frac{5}{7}+\frac{2}{7}+\frac{4}{15}\)
b)\(\frac{5}{9}x\frac{1}{2}x\frac{5}{9}x\frac{6}{4}\)
c)\(\frac{7}{8}:\frac{1}{2}+\frac{9}{8}:\frac{1}{2}\)
d)\(\frac{17}{10}+\frac{1}{2}-\frac{7}{10}\)