1 / x + 1 / (x + 5)= 1 / 6
解:两边乘以 6 x (x + 5)得:
6(x + 5)+ 6 x = x(x + 5)
6 x + 30 + 6 x = x ² + 5 x
30 + 12 x = x ² + 5 x
x ² - 7 x - 30 = 0
(x - 10)(x + 3)= 0
x - 10 = 0 或 x + 3 = 0
x1 = 10 x2 = - 3
1/x+1/(x+5)=1/6
两边乘以 6x(x+5)
6x+30 + 6x = x²+5x
x²-7x-30 =0
(x-10)(x+3) = 0
x= 10 或者 x= -3
1/X+1/(X+5)=1/6
X+5+X=(1/6)*X*(X+5)
12X+30=X^2+5X
X^2-7X-30=0
(X-10)(X+3)=0
X1=10,X2=-3