1. 下列关于x的方程是分式方程的是 ( )
A. $\frac{3 + x}{2} - 3 = \frac{2 + x}{5}$
B. $\frac{2x - 1}{7} = \frac{x}{2}$
C. $\frac{x}{\pi} + 1 = \frac{2 - x}{3}$
D. $\frac{1}{2 + x} = 1 - \frac{2}{x}$
A. $\frac{3 + x}{2} - 3 = \frac{2 + x}{5}$
B. $\frac{2x - 1}{7} = \frac{x}{2}$
C. $\frac{x}{\pi} + 1 = \frac{2 - x}{3}$
D. $\frac{1}{2 + x} = 1 - \frac{2}{x}$
答案
D
2. 将方程$\frac{1}{x - 1} + 3 = \frac{3x}{1 - x}$去分母,两边同乘$(x - 1)$后的式子为 ( )
A. $1 + 3 = 3x(1 - x)$
B. $1 + 3(x - 1) = -3x$
C. $x - 1 + 3 = -3x$
D. $1 + 3(x - 1) = 3x$
A. $1 + 3 = 3x(1 - x)$
B. $1 + 3(x - 1) = -3x$
C. $x - 1 + 3 = -3x$
D. $1 + 3(x - 1) = 3x$
答案
B
3. (2023·淄博)已知$x = 1$是方程$\frac{m}{2 - x} - \frac{1}{x - 2} = 3$的解,那么实数m的值是________.
答案
2
4. (2023·无锡)方程$\frac{3}{x - 2} = \frac{2}{x - 1}$的解是$x =$________.
答案
-1
5. 代数式$\frac{x}{2x - 3}$的值比代数式$\frac{2}{3 - 2x}$的值大4,则$x =$________.
答案
2
6. 解方程:
(1)(2023·泰州)$\frac{x}{2x - 1} = 2 - \frac{3}{1 - 2x}$; (2)$1 - \frac{x - 3}{2x + 2} = \frac{3x}{x + 1}$;
(3)$\frac{x - 2}{x} - \frac{3}{x - 2} = 1$; (4)$\frac{5}{x + 3} + \frac{2}{x^{2} - 9} = \frac{1}{x - 3}$;
(5)$\frac{2x - 5}{x - 2} = \frac{3x - 3}{x - 2} - 3$; (6)$\frac{x}{x - 1} = \frac{3}{2(x - 1)} - 2$.
(1)(2023·泰州)$\frac{x}{2x - 1} = 2 - \frac{3}{1 - 2x}$; (2)$1 - \frac{x - 3}{2x + 2} = \frac{3x}{x + 1}$;
(3)$\frac{x - 2}{x} - \frac{3}{x - 2} = 1$; (4)$\frac{5}{x + 3} + \frac{2}{x^{2} - 9} = \frac{1}{x - 3}$;
(5)$\frac{2x - 5}{x - 2} = \frac{3x - 3}{x - 2} - 3$; (6)$\frac{x}{x - 1} = \frac{3}{2(x - 1)} - 2$.
答案
解:(1)方程两边同乘(2x - 1),得x = 2(2x - 1)+3,
解得x = -$\frac{1}{3}$,
检验:当x = -$\frac{1}{3}$时,2x - 1≠0,
所以x = -$\frac{1}{3}$是原方程的解.
(2)方程两边同乘2(x + 1),得2x + 2-(x - 3)=2×3x,
解得x = 1.
检验:当x = 1时,2(x + 1)≠0,x = 1是原方程的解.
(3)方程两边同乘x(x - 2),得(x - 2)²-3x = x(x - 2),
解得x = $\frac{4}{5}$.
检验:当x = $\frac{4}{5}$时,x(x - 2)≠0,x = $\frac{4}{5}$是原方程的解.
(4)方程两边同乘(x + 3)(x - 3),得5(x - 3)+2 = x + 3,
解得x = 4.
检验:当x = 4时,(x + 3)(x - 3)≠0,x = 4是原方程的解.
(5)方程两边同乘(x - 2),得2x - 5 = 3x - 3-3(x - 2),
解得x = 4.
检验:当x = 4时,x - 2≠0,x = 4是原方程的解.
(6)方程两边同乘2(x - 1),得2x = 3-4(x - 1),
解得x = $\frac{7}{6}$.
检验:当x = $\frac{7}{6}$时,2(x - 1)≠0,x = $\frac{7}{6}$是原方程的解.
解得x = -$\frac{1}{3}$,
检验:当x = -$\frac{1}{3}$时,2x - 1≠0,
所以x = -$\frac{1}{3}$是原方程的解.
(2)方程两边同乘2(x + 1),得2x + 2-(x - 3)=2×3x,
解得x = 1.
检验:当x = 1时,2(x + 1)≠0,x = 1是原方程的解.
(3)方程两边同乘x(x - 2),得(x - 2)²-3x = x(x - 2),
解得x = $\frac{4}{5}$.
检验:当x = $\frac{4}{5}$时,x(x - 2)≠0,x = $\frac{4}{5}$是原方程的解.
(4)方程两边同乘(x + 3)(x - 3),得5(x - 3)+2 = x + 3,
解得x = 4.
检验:当x = 4时,(x + 3)(x - 3)≠0,x = 4是原方程的解.
(5)方程两边同乘(x - 2),得2x - 5 = 3x - 3-3(x - 2),
解得x = 4.
检验:当x = 4时,x - 2≠0,x = 4是原方程的解.
(6)方程两边同乘2(x - 1),得2x = 3-4(x - 1),
解得x = $\frac{7}{6}$.
检验:当x = $\frac{7}{6}$时,2(x - 1)≠0,x = $\frac{7}{6}$是原方程的解.
7. (2024·泰兴一模)已知关于x的方程$\frac{a}{2a - x} = \frac{1}{3}$的解是$x = 1$,则a的值为 ( )
A. 2
B. 1
C. -1
D. -2
A. 2
B. 1
C. -1
D. -2
答案
C
8. (2023·滨江区月考)若$\frac{3x}{x - 1} \cdot |x| = \frac{3x}{x - 1}$,则$x =$ ( )
A. -1
B. -1或0
C. ±1或0
D. ±1
A. -1
B. -1或0
C. ±1或0
D. ±1
答案
B
9. 对于非零实数a,b,规定$a\oplus b = \frac{1}{a} - \frac{1}{b}$. 若$(2x - 1)\oplus2 = 1$,则x的值为________.
答案
$\frac{5}{6}$
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