2/2/19+1/5-5/3/19+(-5/3/19-6/5)
=2/2/19+(1/5-6/5)+(5/3/19-5/3/19)
=19-1+0=18
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TÍNH : 2/3/19+1/5-5/3/19+(-5/3/19-6/5)
1) Tính:a) frac{left(1+frac{17}{1}right).left(1+frac{17}{2}right).left(1+frac{17}{3}right).....left(1+frac{17}{19}right)}{left(1+frac{19}{1}right).left(1+frac{19}{2}right).left(1+frac{19}{3}right).....left(1+frac{19}{17}right)}b) frac{frac{-6}{5}+frac{6}{19}-frac{6}{23}}{frac{9}{5}-frac{9}{19}+frac{9}{23}}c) frac{frac{1}{6}-frac{1}{39}+frac{1}{51}}{frac{1}{8}-frac{1}{52}+frac{1}{68}}d) frac{frac{2}{3}-frac{2}{5}-frac{2}{7}+frac{2}{11}}{frac{13}{3}-frac{13}{5}-frac{13}{7}+frac{13}{11}}e) frac{fra...
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1) Tính:
a) \(\frac{\left(1+\frac{17}{1}\right).\left(1+\frac{17}{2}\right).\left(1+\frac{17}{3}\right).....\left(1+\frac{17}{19}\right)}{\left(1+\frac{19}{1}\right).\left(1+\frac{19}{2}\right).\left(1+\frac{19}{3}\right).....\left(1+\frac{19}{17}\right)}\)
b) \(\frac{\frac{-6}{5}+\frac{6}{19}-\frac{6}{23}}{\frac{9}{5}-\frac{9}{19}+\frac{9}{23}}\)
c) \(\frac{\frac{1}{6}-\frac{1}{39}+\frac{1}{51}}{\frac{1}{8}-\frac{1}{52}+\frac{1}{68}}\)
d) \(\frac{\frac{2}{3}-\frac{2}{5}-\frac{2}{7}+\frac{2}{11}}{\frac{13}{3}-\frac{13}{5}-\frac{13}{7}+\frac{13}{11}}\)
e) \(\frac{\frac{1}{1009}+\frac{1}{1010}+\frac{1}{1011}+...+\frac{1}{2017}}{1-\frac{1}{2}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{2015}-\frac{1}{2016}+\frac{1}{2017}}\)
2) CMR: \(\frac{1}{2^2}+\frac{1}{2^4}+\frac{1}{2^6}+...+\frac{1}{2^{800}}< \frac{1}{3}\)
Bài 1:
a) ( 9/25 - 2.18 ) : 3 4/5 + 0,2 )
b) 3/8 . 19 1/3 - 3/8 . 33 1/3
c) 1 4/23 + 5/21 - 4/23 + 0.5 + 16/21
d) 2^12 . 3^6 - 4^6 . 81 tất cả phần (2^2 . 3)^5 + 8^1 . 3^5
e) 4. ( -1/2)^3 - 2.(-1/2)^2 +3 . (-1/2)+1
Giúp mik nkaBài 1: Tính giá trị của biểu thức ( hợp lí nếu có thể)a/ |-10| : (-2): (-5)+(-3)2b/ 1+ (-2) +3 +(-4) + 5+ (-6)+....+ 21 (-22)c/ frac{3}{4}.frac{5}{9}+frac{3}{4}.frac{4}{9}d/ frac{-4}{17}+frac{5}{19}+frac{-13}{17}+frac{14}{19}+frac{3}{115}e/ left(frac{3}{4}+frac{-7}{2}right).left(frac{10}{11}+frac{2}{22}right)Thanks. Nhanh hộ mik
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Giúp mik nka
Bài 1: Tính giá trị của biểu thức ( hợp lí nếu có thể)
a/ |-10| : (-2): (-5)+(-3)2
b/ 1+ (-2) +3 +(-4) + 5+ (-6)+....+ 21 (-22)
c/ \(\frac{3}{4}.\frac{5}{9}+\frac{3}{4}.\frac{4}{9}\)
d/ \(\frac{-4}{17}+\frac{5}{19}+\frac{-13}{17}+\frac{14}{19}+\frac{3}{115}\)
e/ \(\left(\frac{3}{4}+\frac{-7}{2}\right).\left(\frac{10}{11}+\frac{2}{22}\right)\)
Thanks. Nhanh hộ mik
\(\dfrac{3}{8}\cdot27\dfrac{1}{5}-51\dfrac{1}{5}\cdot\dfrac{3}{8}+19\)
\(\dfrac{35\dfrac{1}{6}}{\left(\dfrac{-4}{5}\right)}-\dfrac{46\dfrac{1}{6}}{\left(\dfrac{-4}{5}\right)}\)
\(\dfrac{\left(\dfrac{-3}{4}+\dfrac{2}{5}\right)}{\dfrac{3}{7}+\dfrac{\left(\dfrac{3}{5}+\dfrac{-1}{4}\right)}{\dfrac{3}{7}}}\)
thực hiện phép tính
a. \(\dfrac{11}{21}+\dfrac{-2}{7}+\dfrac{10}{21}+\left(-1\dfrac{1}{5}\right)+\dfrac{-5}{7}\)
\(b.\left(0.25\right)^5.\left(-5\dfrac{5}{9}\right).\left(-4\right)^5\)
\(c.\dfrac{3}{22}.19\dfrac{1}{7}+\dfrac{3}{22}.2\dfrac{6}{7}-\sqrt{36}\)
CM:
\(\dfrac{3}{1^2.2^2}+\dfrac{5}{2^2.3^2}+\dfrac{7}{3^2.4^2}+...+\dfrac{19}{9^2+10^2}< 1\)
Chứng minh:
\(\dfrac{3}{1^2.2^2}+\dfrac{5}{2^2.3^2}+\dfrac{7}{3^2.4^2}+...+\dfrac{19}{9^2.10^2}< 1\)
Chứng minh rằng: \(\frac{3}{1^2.2^2}+\frac{5}{2^2.3^2}+\frac{7}{3^2.4^2}+......+\frac{19}{9^2.10^2}< 1\)