(15-2x-x^2)/(x-4)=0

解答

\frac{15 - 2 x - x ^{2}}{x - 4} = 0

x = - 5, x = 3

求解步骤

\frac{15 - 2 x - x ^{2}}{x - 4} = 0

\frac{f ( x )}{g ( x )} = 0 \Rightarrow f (x) = 0

15 - 2 x - x^{2} = 0

解

15 - 2 x - x^{2} = 0 : x = - 5, x = 3

x = - 5, x = 3

验证解

找到无定义的点（奇点）:

x = 4

将不在定义域的点与解相综合:

x = - 5, x = 3

\frac{3 z - 6}{7 - 2 z} = \frac{1.2}{3.2}

\frac{8}{x ^{2}} + 1 = \frac{9}{x}

\frac{1}{x + 9} - 1 = \frac{x}{x + 9}

\frac{1}{2 x} + \frac{3}{x + 7} = \frac{- 1}{x}

\frac{2}{x} + \frac{5}{3 x} = 5