化简 5/(x+3)+x/(x^2-9)

解答

化简

\frac{5}{x + 3} + \frac{x}{x ^{2} - 9}

\frac{6 x - 15}{( x + 3 ) ( x - 3 )}

求解步骤

\frac{5}{x + 3} + \frac{x}{x ^{2} - 9}

x + 3, x^{2} - 9

的最小公倍数:

(x + 3) (x - 3)

根据最小公倍数调整分式

= \frac{5 ( x - 3 )}{( x + 3 ) ( x - 3 )} + \frac{x}{( x + 3 ) ( x - 3 )}

使用分式法则:

\frac{a}{c} + \frac{b}{c} = \frac{a + b}{c}

= \frac{5 ( x - 3 ) + x}{( x + 3 ) ( x - 3 )}

化简

5 (x - 3) + x : 6 x - 15

= \frac{6 x - 15}{( x + 3 ) ( x - 3 )}

s im pl i f y \frac{\frac{- 7}{5}}{( - \frac{14}{3} )}

s im pl i f y 3 24 x^{4}

s im pl i f y 7^{l o g_{7} (2)}

s im pl i f y 18 \times \frac{2}{3}

7 \frac{2}{3} + 4 \frac{2}{5} + 2 \frac{1}{15}