Tính : \(15\frac{3}{40}.\frac{594}{40}-\frac{3}{40}.\left(-14\right)+\frac{3}{40}.\frac{23}{20}\)
Những câu hỏi liên quan
\(a,18\frac{2}{17}+\frac{15}{23}-1\frac{19}{17}+\frac{3}{19}-\frac{38}{23}\)
\(b,\left(\frac{5}{7}.0,6-5:3\frac{1}{2}\right).\left(\frac{40}{100}-1,4\right).\left(-2\right)^3\)
Tính :
a) \(1\frac{7}{20}:2,7+2,7:1,35+\left(0,4:2\frac{1}{2}\right).\left(4,8-1\frac{3}{40}\right)\)
b) \(\left[\left(6\frac{3}{5}-3\frac{3}{14}\right):5\frac{5}{6}\right]:\left[\left(21-1,25\right):2,5\right]\)
tìm x ,biết:a)frac{2}{left(x+2right).left(x+4right)}+frac{4}{left(x+4right).left(x+8right)}+frac{6}{left(x+8right).left(x+14right)}frac{x}{left(x+2right).left(x+14right)}b)frac{x+1}{10}+frac{x+1}{11}+frac{x+1}{12}frac{x+1}{13}+frac{x+1}{14}c)left(x-2right)^2frac{38}{25}+frac{9}{10}-frac{11}{15}+frac{13}{21}-frac{15}{28}+frac{17}{36}-..+frac{197}{1851}-frac{199}{1950}giúp mk vs, hu hu
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tìm x ,biết:
a)\(\frac{2}{\left(x+2\right).\left(x+4\right)}+\frac{4}{\left(x+4\right).\left(x+8\right)}+\frac{6}{\left(x+8\right).\left(x+14\right)}=\frac{x}{\left(x+2\right).\left(x+14\right)}\)
b)\(\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}=\frac{x+1}{13}+\frac{x+1}{14}\)
c)\(\left(x-2\right)^2=\frac{38}{25}+\frac{9}{10}-\frac{11}{15}+\frac{13}{21}-\frac{15}{28}+\frac{17}{36}-..+\frac{197}{1851}-\frac{199}{1950}\)
giúp mk vs, hu hu
a) \(\frac{2}{\left(x+2\right).\left(x+4\right)}+\frac{4}{\left(x+4\right).\left(x+8\right)}+\frac{6}{\left(x+8\right).\left(x+14\right)}=\frac{x}{\left(x+2\right).\left(x+14\right)}\)
\(\Rightarrow\frac{1}{x+2}-\frac{1}{x+4}+\frac{1}{x+4}-\frac{1}{x+8}+\frac{1}{x+8}-\frac{1}{x+14}=\frac{x}{\left(x+2\right).\left(x+14\right)}\)
\(\Rightarrow\frac{1}{x+2}-\frac{1}{x+14}=\frac{x}{\left(x+2\right).\left(x+14\right)}\)
\(\Rightarrow\frac{x+14}{\left(x+2\right).\left(x+14\right)}-\frac{x+2}{\left(x+2\right).\left(x+14\right)}=\frac{x}{\left(x+2\right).\left(x+14\right)}\)
\(\Rightarrow\frac{x+14-x+2}{\left(x+2\right).\left(x+14\right)}=\frac{x}{\left(x+2\right).\left(x+14\right)}\)
\(\Rightarrow\frac{16}{\left(x+2\right).\left(x+4\right)}=\frac{x}{\left(x+2\right).\left(x+14\right)}\)
\(\Rightarrow x=16\)
Vậy x = 16
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\(b,\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}=\frac{x+1}{13}+\frac{x+1}{14}\)
\(\Leftrightarrow\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}-\frac{x+1}{13}-\frac{x+1}{14}=0\)
\(\Leftrightarrow\left(x+1\right)\left(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}\right)=0\)
\(\Leftrightarrow x+1=0\left(vì\frac{1}{10}+\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}\ne0\right)\)
\(\Leftrightarrow x=-1\)
\(\text{Vậy }x=-1\)
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tìm x ,biết:a)frac{2}{left(x+2right)left(x+4right)}+frac{4}{left(x+4right)left(x+8right)}+frac{6}{left(x+8right)left(x+14right)}frac{x}{left(x+2right)left(x+14right)}b)frac{x+1}{10}+frac{x+1}{11}+frac{x+1}{12}frac{x+1}{13}+frac{x+1}{14}c)(x-2)2frac{38}{25}+frac{9}{10}-frac{11}{15}+frac{13}{21}-frac{15}{28}+frac{17}{36}-...+frac{197}{4851}-frac{199}{4950}giúp mk với ,huhu
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tìm x ,biết:
a)\(\frac{2}{\left(x+2\right)\left(x+4\right)}+\frac{4}{\left(x+4\right)\left(x+8\right)}+\frac{6}{\left(x+8\right)\left(x+14\right)}=\frac{x}{\left(x+2\right)\left(x+14\right)}\)
b)\(\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}=\frac{x+1}{13}+\frac{x+1}{14}\)
c)(x-2)2=\(\frac{38}{25}+\frac{9}{10}-\frac{11}{15}+\frac{13}{21}-\frac{15}{28}+\frac{17}{36}-...+\frac{197}{4851}-\frac{199}{4950}\)
giúp mk với ,huhu
b. (x+1)(1/10+1/11+1/12-1/13-1/14)=0
x+1=0 (vì : 1/10+1/11+1/12-1/13-1/14>0)
x=-1
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a ) thực hiện phép tính bằng cách nhanh nhất
\(\left(-\frac{40}{51}.0,32.\frac{17}{20}\right):\frac{64}{75}\)
\(-1\frac{5}{7}.15+\frac{2}{7}.\left(-15\right)+\left(-105\right).\left(\frac{2}{3}-\frac{4}{5}+\frac{1}{7}\right)\)
1/Tính A=\(0,5^3+1^3+1,5^3+...+5^3\)
biết \(1^3+2^3+3^3+...+10^3=3025\)
2/Tính:
\(\left(\frac{16}{3}-\sqrt{\frac{40}{9}}^{^0}\right)\left(\frac{17}{3}-\sqrt{\frac{40}{9}}^0\right)...\left(\frac{30}{3}-\sqrt{\frac{40}{9}}^0\right)\)
cho các biểu thức
A=\(\left(\frac{1}{8\cdot14}+\frac{1}{14\cdot20}+\frac{1}{20\cdot26}+...+\frac{1}{50\cdot56}\right)\)
\(B=\left(\frac{45}{12\cdot21}+\frac{45}{21\cdot30}+\frac{40}{24\cdot34}-\frac{40}{34\cdot44}-\frac{40}{44\cdot54}-\frac{40}{54\cdot64}\right)\)
Chứng minh rằng:\(\frac{A}{B}< \frac{1}{8}\)
Giúp bài này hộ mk nha. Mk đg cần gấp huhu. Chú ý dấu chấm là nhân nha. a) 2016+frac{0,2+0,375+frac{5}{11}}{-0,3+frac{9}{10}-frac{15}{22}}b)frac{1,11+0,19-13,2}{2,06+0,54}-left(frac{1}{2}+frac{1}{3}right):2c)-1frac{5}{7}.15+frac{2}{7}.left(-15right)+left(-105right).left(frac{2}{3}-frac{4}{5}+frac{1}{7}right)
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Giúp bài này hộ mk nha. Mk đg cần gấp huhu
. Chú ý dấu chấm là nhân nha.
a) \(2016+\frac{0,2+0,375+\frac{5}{11}}{-0,3+\frac{9}{10}-\frac{15}{22}}\)
b)\(\frac{1,11+0,19-13,2}{2,06+0,54}-\left(\frac{1}{2}+\frac{1}{3}\right):2\)
c)\(-1\frac{5}{7}.15+\frac{2}{7}.\left(-15\right)+\left(-105\right).\left(\frac{2}{3}-\frac{4}{5}+\frac{1}{7}\right)\)
a: \(=2016+\dfrac{\dfrac{1}{5}+\dfrac{3}{8}+\dfrac{5}{11}}{-\dfrac{3}{10}+\dfrac{9}{10}-\dfrac{15}{22}}=2016+\dfrac{453}{440}:\dfrac{-9}{110}\)
\(=2016-\dfrac{151}{12}=\dfrac{24343}{12}\)
b: \(=\dfrac{1,3-13.2}{2.6}-\dfrac{5}{6}:2\)
\(=\dfrac{-119}{26}-\dfrac{5}{12}=\dfrac{-779}{156}\)
c: \(=15\left(-1-\dfrac{5}{7}-\dfrac{2}{7}\right)+\left(-105\right)\cdot\dfrac{1}{105}\)
\(=-30-1=-31\)
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3 tháng 7 2019 lúc 8:33
Bà 18 : Thực hiện các phép tính sau = cách hợp lý nhất :
a) ( -40/51 . 0,32 . 17/20 ) : 64/75
b) -10/11 . 8/9 + 7/18 . 10/11
c) 3/14 : 1/28 - 13/21 : 1/28 + 29/42 : 1/28 - 8
d) \(-1\frac{5}{7}.15+\frac{2}{7}.\left(-15\right)+\left(-105\right).\left(\frac{2}{3}-\frac{4}{5}+\frac{1}{7}\right)\)