(x+1)/(x+3)= 2/x

解答

\frac{x + 1}{x + 3} = \frac{2}{x}

x = 3, x = - 2

求解步骤

\frac{x + 1}{x + 3} = \frac{2}{x}

使用分式交叉相乘

(x + 1) x = (x + 3) \cdot 2

解

(x + 1) x = (x + 3) \cdot 2 : x = 3, x = - 2

x = 3, x = - 2

验证解

找到无定义的点（奇点）:

x = - 3, x = 0

将不在定义域的点与解相综合:

x = 3, x = - 2

\frac{5}{x} - \frac{1}{2 x} = \frac{9}{x ^{2}}

\frac{1}{x + 2} - \frac{1}{x + 3} = \frac{1}{2}

\frac{4}{( 2 x + 3 )} = \frac{3}{( x - 3 )}

\frac{3}{x + 1} + \frac{1}{x - 1} = 2

\frac{x + 2}{2 x} - \frac{x}{4} = \frac{1}{2}