Question

方程Ig(x^2+4x-26)-Ig(x-3)=1的解为

Answer 1

Ig【(x^2+4x-26)/(x-3)】= 1

(x^2+4x-26)/(x-3) = 10

x²-6x+4=0

x=3±√5

又依题意有：x-3＞0 x²+4x-26＞0

所以 x=3-√5 不合题意.

故正确的解为：x=3+√5