\(\Leftrightarrow\dfrac{1}{3}x-\dfrac{1}{3}\cdot\dfrac{3}{2}-2x+1=0\)
=>-5/3x+1/2=0
=>-5/3x=-1/2
hay x=3/10
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Các câu hỏi tương tự
Phương trình : \(\dfrac{1}{\left(x-1\right)\left(x-2\right)}+\dfrac{1}{\left(x-2\right)\left(x-3\right)}=\dfrac{1}{\left(x-3\right)\left(x-4\right)}+\dfrac{1}{\left(x-1\right)\left(x-4\right)}\)
\(\dfrac{2}{\left(x-1\right)\left(x-3\right)}+\dfrac{5}{\left(x-3\right)\left(x-8\right)}+\dfrac{12}{\left(x-8\right)\left(x-20\right)}+\dfrac{1}{x-20}=\dfrac{3}{4}\)
Tìm x
Rút gọn:
\(\left[\dfrac{3}{x+1}+\left(\dfrac{3}{x+1}-\dfrac{x}{1+2x+x^2}\right):\dfrac{2x^3+3x^2}{x+1}\right]:\dfrac{3x+1}{x^3+x^2}:\left(x-1\right)\)
Rút gọn:
\(A=\left[\left(\dfrac{3}{1+x}-\dfrac{x}{x^2+x+1}\right):\dfrac{2x^2+3x}{x+1}+\dfrac{3}{x+1}\right]\cdot\dfrac{x^2+x}{1+3x}\)
\(B=\left[\dfrac{a}{2a-6}-\dfrac{a^2}{a^2-9}+\dfrac{a}{2a-9}\cdot\left(\dfrac{3}{a}+\dfrac{1}{3-a}\right)\right]:\dfrac{a^2-5a-6}{18-2a^2}\)
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}+1,2right|+1dfrac{2}{3}:6
2. Tìm x, biết:
a. dfrac{2}{3}x-dfrac{1}{3}xdfrac{5}{12}
b. left(x-dfrac{12}{7}right):1dfrac{1}{5}dfrac{4}{7}
c. dfrac{2}{5}+left|x+1right|dfrac{3}{4}
3. Tìm x, y biết:
a. dfrac{x}{18}dfrac{y}{15}và x - y -30
b. 7...
Đọc tiếp
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
B = 1+ \(\dfrac{1}{2}\left(1+2\right)+\dfrac{1}{3}\left(1+2+3\right)+\dfrac{1}{4}\left(1+2+3+4\right)+.......+\dfrac{1}{x}\left(1+2+3+4+....+x\right)\)
Tìm số nguyên dương x để B = 115
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(-6right)
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. 1dfrac{2}{5}x+dfrac{3}{7}dfrac{4}{5}
b. |x - 1,5| 2
c. df...
Đọc tiếp
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 nghiệm của các đa thức sau:
A-dfrac{2}{3}x-dfrac{5}{9} Bx^2-dfrac{4}{25} Cdfrac{1}{2}x^3+dfrac{4}{27} Dx^3-dfrac{1}{8}x
E-dfrac{16}{81}+x^4 F-x.left(-2x+3right).left(1-x^3right) I2.left(2-xright)+dfrac{1}{2}left(x-2right)^2 Gx^{100}-8.x^{97}
Đọc tiếp
Tìm nghiệm của các đa thức sau:
\(A=-\dfrac{2}{3}x-\dfrac{5}{9}\) \(B=x^2-\dfrac{4}{25}\) \(C=\dfrac{1}{2}x^3+\dfrac{4}{27}\) \(D=x^3-\dfrac{1}{8}x\)
\(E=-\dfrac{16}{81}+x^4\) \(F=-x.\left(-2x+3\right).\left(1-x^3\right)\) \(I=2.\left(2-x\right)+\dfrac{1}{2}\left(x-2\right)^2\) \(G=x^{100}-8.x^{97}\)
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):\(\left(x+1\dfrac{3}{4}\right)< 0\)