\(\dfrac{1}{4}+\dfrac{1}{3}:3x=-5\)
\(\dfrac{1}{3}:3x=-\dfrac{21}{4}\)
\(3x=-\dfrac{4}{63}=>x=-\dfrac{4}{189}\)
Chúc bn học tốt
Tìm x,y biết:
a) \(-\dfrac{1}{2}\left(3-2x\right)-7=5-\dfrac{1}{3}\left(x-\dfrac{4}{5}\right)\)
b)\(\left(5-\dfrac{3x}{2}\right):-1\dfrac{3}{8}=-7\dfrac{1}{3}\)
c)\(\left(2+3x\right)^2+\left|3x+2y\right|=0\)
a\(\dfrac{5}{6}x-\dfrac{2}{3}=3\dfrac{1}{2}\)
b\(\dfrac{4}{5}-\dfrac{3}{4}\div x=0,3\)
c\(\dfrac{-3}{2}-\dfrac{1}{4}x=1\dfrac{1}{3}-0,2x\)
d\(\left|\dfrac{3}{5}x+\dfrac{4}{3}\right|:\dfrac{2}{3}-0,5=1\dfrac{1}{2}\)
e\(\dfrac{4x-5}{2-3x}=\dfrac{3}{4}\)
giúp mình nhé
tìm x biết
a) \(\dfrac{2x-3}{3}+-\dfrac{3}{2}=\dfrac{5-2x}{6}-\dfrac{1}{2}\)
b) \(\left(3x-\dfrac{1}{2}\right).\left(3-\dfrac{1}{2}x\right).\left(1+\dfrac{3}{4}:x\right)=0\)
c) \(\left(3-\dfrac{9}{10}-|x+2|\right):\left(\dfrac{19}{20}-1-\dfrac{2}{3}\right)+\dfrac{4}{5}=1\)
tìm x biết
\(\left(3\dfrac{1}{2}+2x\right).2\dfrac{2}{3}=5\dfrac{1}{3}\)
\(\dfrac{3}{4}-2.\left|2x-\dfrac{2}{3}\right|=2\)
\(\left(0.6-\dfrac{1}{2}\right).\dfrac{3}{4}-\left(-1\right)=\dfrac{1}{3}\)
\(\left(3x-1\right).\left(-\dfrac{1}{2}x+5\right)=0\)
\(\dfrac{1}{4}+\dfrac{1}{3}:\left(2x-1\right)=-5\)
\(\left(2x+\dfrac{3}{5}\right)^2-\dfrac{9}{25}=0\)
\(-5.\left(x+\dfrac{1}{5}\right)-\dfrac{1}{2}.\left(x-\dfrac{2}{3}\right)=\dfrac{3}{2}x-\dfrac{5}{6}\)
Tìm số x , biết
a) \(\dfrac{2}{3}x-\dfrac{3}{2}x=\dfrac{5}{12}\)
b) \(\dfrac{2}{5}+\dfrac{3}{5}.\left(3x-3,7\right)=-\dfrac{53}{10}\)
c) \(\dfrac{7}{9}:\left(2+\dfrac{3}{4}x\right)+\dfrac{5}{9}=\dfrac{23}{27}\)
d) \(\dfrac{-2}{3}.x+\dfrac{1}{5}=\dfrac{3}{10}\)
e) \(\left|x\right|-\dfrac{3}{4}=\dfrac{5}{3}\)
f) \(\left|2x-\dfrac{1}{3}\right|+\dfrac{5}{6}=1\)
Bài 1:Tìm x biết:
a)\(\dfrac{6}{5}\)-2 |1- 3x| =1\(\dfrac{2}{3}\)
b) (2,8x +50) : \(\dfrac{-3}{2}\) =51
c) \(\dfrac{x-2}{-2}\)=\(\dfrac{x+4}{3}\)
d) 4(3-2x) -5(x-1)=12
Bài 2: Chứng minh:
\(\dfrac{1}{3^2}+\dfrac{1}{4^2}+\dfrac{1}{5^2}+...+\dfrac{1}{100^2}< \dfrac{1}{2}\)
\(\left(2x-3\right)\left(6-2x\right)=0\)
\(\dfrac{1}{3}x+\dfrac{2}{5}\left(x-1\right)=0\)
\(\left(3x-1\right)\left(-\dfrac{1}{2}x+5\right)=0\)
\(\dfrac{x}{5}=\dfrac{2}{3}\)
\(\dfrac{x}{3}-\dfrac{1}{2}=\dfrac{1}{5}\)
\(\dfrac{x}{5}-\dfrac{1}{2}=\dfrac{6}{10}\)
\(\dfrac{x+3}{15}=\dfrac{1}{3}\)
\(\dfrac{x-12}{4}=\dfrac{1}{2}\)
Tìm x.( giúp mk với ! )
a) x:\(4\dfrac{1}{3}=-2,5\)
b) x: \(\dfrac{-3}{5}=\dfrac{-10}{21}\)
c) \(\dfrac{2}{3}x-\dfrac{1}{2}=\dfrac{1}{10}\)
d) \(\dfrac{1}{2}x-\dfrac{1}{2}=\dfrac{5}{2}\)
e) \(\dfrac{-2}{3}-\dfrac{1}{3}\left(2x-5\right)=\dfrac{3}{2}\)
g) \(\dfrac{2}{5}.x+\dfrac{1}{2}=\dfrac{-3}{4}\)
h)\(\left(2x-2\dfrac{4}{5}\right):3\dfrac{1}{8}=1\dfrac{3}{5}\)
i)\(3,2x-\left(\dfrac{4}{5}+\dfrac{2}{3}\right):\dfrac{2}{3}=\dfrac{7}{20}\)
k) \(\left(\dfrac{3x}{7}+1\right):\left(-4\right)=\dfrac{-1}{28}\)
Đúng mình tick cho ạ, giúp mình với !
Chứng minh rằng:
1) B =\(\dfrac{1}{4}+\dfrac{1}{5}+\dfrac{1}{6}+...+\dfrac{1}{19}>1\)
2) \(A=\dfrac{1}{5}+\dfrac{2}{5^2}+\dfrac{3}{5^3}+\dfrac{4}{5^4}+...+\dfrac{500}{5^{500}}<100\)
3) \(C=\dfrac{1}{2^3}+\dfrac{1}{3^3}+\dfrac{1}{4^3}+\dfrac{1}{5^3}+...+\dfrac{1}{500^3}<\dfrac{1}{4}\)
4) \(D=\dfrac{4}{3}+\dfrac{10}{9}+\dfrac{28}{27}+...+\dfrac{3^{98}+1}{3^{98}}<100\)
Làm giúp mình sớm nha! Thanks.
