tìm x biết\(\frac{x+3}{3}=\frac{27}{x+3}\)
Tìm x biết
\(|x+\frac{1}{3}|+\frac{4}{5}=|\left(-3,2\right)+\frac{2}{5}|+\left(27-\frac{3}{5}\right)\left(27-\frac{3^2}{6}\right)\left(27-\frac{3^3}{7}\right)...\left(27-\frac{3^{2010}}{2014}\right)\)
\(\left|x+\frac{1}{3}\right|+\frac{4}{5}=\left|-3,2+\frac{2}{5}\right|+\left(27-\frac{3}{5}\right)\left(27-\frac{3^2}{6}\right)...\left(27-\frac{3^5}{9}\right)...\left(27-\frac{3^{2010}}{2014}\right)\)
\(\Leftrightarrow\left|x+\frac{1}{3}\right|+\frac{4}{5}=\frac{14}{5}+\left(27-\frac{3^2}{6}\right)\left(27-\frac{3^3}{7}\right)...\left(27-27\right)...\left(27-\frac{3^{2010}}{2014}\right)\)
\(\Leftrightarrow\left|x+\frac{1}{3}\right|+\frac{4}{5}=\frac{14}{5}\)
\(\Leftrightarrow\left|x+\frac{1}{3}\right|=2\)
\(\Rightarrow\hept{\begin{cases}x+\frac{1}{3}=2\\x+\frac{1}{3}=-2\end{cases}\Rightarrow\hept{\begin{cases}x=\frac{5}{3}\\x=-\frac{7}{3}\end{cases}}}\)
bạn ơi, có một chỗ chưa chuẩn .bạn kiểm tra lại giú mình. chỗ vế trái bạn thiếu \(\left(27-\frac{3}{5}\right)\). bạn bổ sung vào cho đúng nhé. dù sao vẫn cảm ơn bạn.
a) Tìm số nguyên x, biết:
\(\frac{x}{9}=\frac{-12}{27}\)
b) Tìm số nguyên x, biết: 12 - ( x - 4 ) = 17
c) Tìm y biết: \(\left(1\frac{2}{3}+2\frac{2}{3}y\right).\frac{10}{11}=2\frac{3}{11}\)
a) Ta có: \(\frac{x}{9}=\frac{-12}{27}\)
=> \(27.x=-12.9\)
=> \(27x=-108\)
=> \(x=108:27\)
=>\(x=4\)
tìm x biết \(\frac{3-x}{2}=\frac{x+27}{3}\)
=> \(\frac{3\left(3-x\right)}{2.3}=\frac{2\left(x+27\right)}{2.3}\)=> 3(3-x) = 2(x+27) => 9 - 3x = 2x + 54 => 9 - 54 = 2x + 3x => -45 = 5x => x = -45/5 = - 9
Vậy x = - 9
Tìm x biết:
a)\(\frac{x-2}{4}=\frac{x+5}{-3}\)
b) \(\frac{x}{3}=\frac{27}{x}\)
Giúp mình với
a)
\(\frac{x-2}{4}=\frac{x+5}{-3}\)
\(\Rightarrow\frac{-3.\left(x-2\right)}{4.\left(-3\right)}=\frac{4.\left(x+5\right)}{4.\left(-3\right)}\)
\(\Rightarrow\frac{-3x+6}{-12}=\frac{4x+20}{-12}\)
\(\Rightarrow-3x+6=4x+20\)
\(\Rightarrow-3x-4x=20-6\)
\(\Rightarrow-7x=14\)
\(\Rightarrow x=-2\)
b)
\(\frac{x}{3}=\frac{27}{x}\)
\(\Rightarrow x.x=3.27\)
\(\Rightarrow x^2=81\)
\(\Rightarrow\orbr{\begin{cases}x=9\\x=-9\end{cases}}\)
T**k mik nhé!
Tìm x biết : \(\left(\frac{1}{3}\right)^x\left(\frac{1}{9}\right)^x\left(\frac{1}{27}\right)^x\left(\frac{1}{81}\right)^x\left(\frac{1}{243}\right)^x=\left(-\frac{1}{3}\right)^{30}\)
Tìm số nguyễn x biết rằng: \(\frac{3}{7}.\frac{46}{3}+\frac{3}{7}.\frac{27}{5}\le x\le\left(\frac{7}{2}:7-\frac{13}{12}\right).\left(\frac{-7}{3}\right)\)
\(\Leftrightarrow\dfrac{46}{7}+\dfrac{81}{35}< =x< =\dfrac{49}{36}\)
\(\Leftrightarrow\dfrac{311}{35}< =x< =\dfrac{49}{36}\)
\(\Leftrightarrow x\in\varnothing\)
Tìm x biết :
a, \(\frac{27}{x+1}=\frac{x+1}{3}\)
b, \(\left(x-\frac{2}{9}\right)^3=\left(\frac{2}{3}\right)^6\)
\(a,\frac{27}{x+1}=\frac{x+1}{3}\)
\(\Leftrightarrow27.3=\left(x+1\right)\left(x+1\right)\)
\(\Leftrightarrow81=\left(x+1\right)^2\)
\(\Rightarrow\orbr{\begin{cases}\left(x+1\right)^2=9^2\\\left(x+1\right)^2=\left(-9\right)^2\end{cases}\Rightarrow\orbr{\begin{cases}x+1=9\\x+1=-9\end{cases}}\Rightarrow\orbr{\begin{cases}x=8\\x=-10\end{cases}}}\)
Vậy \(x\in\left\{8;-10\right\}\)
a)\(\frac{27}{x+1}=\frac{x+1}{3}\)
Ta có : 27 . 3 = (x + 1)(x + 1)
=> 81 = (x + 1)2
=> 92 = (x + 1)2
=> \(\orbr{\begin{cases}x+1=9\\x+1=-9\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=8\\x=-10\end{cases}}\)
\(b,\left(x-\frac{2}{9}\right)^3=\left(\frac{2}{3}\right)^6\)
\(\Leftrightarrow\left(x-\frac{2}{9}\right)^3=\left(\frac{4}{9}\right)^3\)
\(\Rightarrow x-\frac{2}{9}=\frac{4}{9}\)
\(\Rightarrow x=\frac{6}{9}=\frac{2}{3}\)
Vậy \(x=\frac{2}{3}\)
Tìm x biết :
\(\frac{1}{1×2×3×4}+\frac{1}{2×3×4×5}+\frac{1}{3×4×5×6}+...+\frac{1}{27×28×29×30}×x=-3\)
Tìm x, biết: \(\frac{27}{x+x}\)=\(\frac{x+2}{3}\)