a ) \(\left|x\right|-\dfrac{3}{4}=0\)
\(\Leftrightarrow\left|x\right|=\dfrac{3}{4}\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{4}\\x=-\dfrac{3}{4}\end{matrix}\right.\)
Vậy ............
b ) \(\dfrac{3}{4}+\dfrac{2x}{5}=\dfrac{29}{60}\)
\(\Leftrightarrow\dfrac{45}{60}+\dfrac{24x}{60}=\dfrac{29}{60}\)
\(\Leftrightarrow45+24x=29\)
\(\Leftrightarrow x=-\dfrac{2}{3}.\)
Vậy..
Tìm các số hữu tỷ x,biết rằng:
a,\(\left(x-\dfrac{5}{3}\right):-1\dfrac{3}{4}=0\)
b,\(\left(x-\dfrac{1}{5}\right)\left(1\dfrac{3}{5}+2x\right)=0\)
c,\(\left(x-\dfrac{4}{7}\right):\left(x+\dfrac{1}{2}\right)>0\)
d,(2x-3):\(\left(x+1\dfrac{3}{4}\right)< 0\)
ĐỀ 2:
1. Tính:
A. \(\left(-\dfrac{2}{3}\right)^2+\left(-\dfrac{7}{8}\right)+\left(-\dfrac{11}{12}\right)\)
B. \(\left(\dfrac{-1}{3}\right)^2:\dfrac{1}{6}-2.\left(\dfrac{-1}{2}\right)^3\)\
C. \(\dfrac{-1}{5}-\left(\dfrac{1}{2}+\dfrac{3}{4}\right)^2:\dfrac{5}{8}\)
D. \(\left|\dfrac{-3}{2}+1,2\right|+1\dfrac{2}{3}:6\)
2. Tìm x, biết:
a. \(\dfrac{2}{3}x-\dfrac{1}{3}x=\dfrac{5}{12}\)
b. \(\left(x-\dfrac{12}{7}\right):1\dfrac{1}{5}=\dfrac{4}{7}\)
c. \(\dfrac{2}{5}+\left|x+1\right|=\dfrac{3}{4}\)
3. Tìm x, y biết:
a. \(\dfrac{x}{18}=\dfrac{y}{15}\)và x - y = -30
b. 7x = 9x và 10x - 8x = 68
c. \(\left(x-\dfrac{1}{2}\right)^{50}+\left(y+\dfrac{1}{3}\right)^{40}=0\)
* Lm nhanh nha
ĐỀ 1:
1. Tính:
a. \(\dfrac{7}{23}\left[\left(\dfrac{-8}{6}\right)-\dfrac{45}{18}\right]\)
b. \(\dfrac{1}{5}:\dfrac{1}{10}-\dfrac{1}{3}\left(\dfrac{6}{5}-\dfrac{9}{4}\right)\)
c. \(\dfrac{3}{5}.\left(\dfrac{-8}{3}\right)-\dfrac{3}{5}:\left(-6\right)\)
d. \(\dfrac{1}{2}\left(\dfrac{4}{3}+\dfrac{2}{5}\right)-\dfrac{3}{4}\left(\dfrac{8}{9}+\dfrac{16}{3}\right)\)
e. \(\dfrac{6}{7}:\left(\dfrac{3}{26}-\dfrac{3}{13}\right)+\dfrac{6}{7}\left(\dfrac{1}{10}-\dfrac{8}{5}\right)\)
2. Tìm x, biết:
a. \(1\dfrac{2}{5}x+\dfrac{3}{7}=\dfrac{4}{5}\)
b. |x - 1,5| = 2
c. \(\dfrac{4}{5}-\left|x-\dfrac{1}{6}\right|=\dfrac{2}{3}\)
d. 3x . 2x = 216
e. \(\dfrac{1}{2}\left(x-\dfrac{1}{3}\right)+\dfrac{-1}{2}=\dfrac{3}{4}\)
* Lm nhanh nha
Ths you <3
Tìm x, biết rằng:
a) \(\left(x-\dfrac{3}{4}\right)^2=0\)
b) \(\left(x-3\right)^2=1\)
c) \(\left(2x+1\right)^3=-8\)
d) \(\left(x-\dfrac{1}{4}\right)^2=\dfrac{1}{4}\)
Tìm số nguyên x biết:
a. \(-4\dfrac{3}{5}.2\dfrac{4}{23}\)<x<\(-2\dfrac{3}{5}:1\dfrac{6}{15}\) b. \(-4\dfrac{1}{3}.\left(\dfrac{1}{2}-\dfrac{1}{6}\right)< x< -\dfrac{2}{3}\left(\dfrac{1}{3}-\dfrac{1}{2}-\dfrac{3}{4}\right)\)
Tinh x:
a)\(\dfrac{3}{4}+\dfrac{1}{4}:x=\dfrac{2}{5}\)
b)\(\dfrac{1}{4}+\dfrac{1}{3}:2x=-5\)
c)\(-2+\left|x+\dfrac{1}{5}\right|=\dfrac{9}{10}\)
Tìm x , biết :
a, \(x\left(\dfrac{1}{5}+\dfrac{1}{4}\right)-\left(\dfrac{1}{7}+\dfrac{1}{8}\right)=0.\)
b, \(\left(3x-1\right)^5=\left(3x-1\right)^3\)
Tìm x,biết:
\(\left(\dfrac{5}{6}-\dfrac{3}{4}\right):\dfrac{-2x}{3}=\dfrac{-12}{9}\)
Tìm x biết:
a) \(\dfrac{x}{2}-\dfrac{1}{x}=\dfrac{1}{12}\)
b) 2x - 3 < 0
c) (2x-4) (9-3x) >0
d)\(\dfrac{2x}{3}-\dfrac{3}{4}\) > 0
e) (\(\dfrac{3}{4}\) - 2x)(\(\dfrac{-3}{5}+\dfrac{2}{-61}-\dfrac{17}{51}\)) nhỏ hơn hoặc bằng 0
f)( \(\dfrac{3}{2x}-4\)) . \(\dfrac{5}{3}\)
