(x^2-3)/(lxl-3)=0,x=?
问题描述:
(x^2-3)/(lxl-3)=0,x=?
答
(x²-3)/(|x|-3)=0
[(x+3)(x-3)]/(|x|-3)=0
当x≥0时,方程可化为:
[(x+3)(x-3)]/(x-3)=0
x+3=0
x=-3(舍去)
当x(x-3)(x+3)=x^2-9不等于x^2-3(x²-3)/(|x|-3)=0
x²-3=0且|x|-3≠0
x²=3且x≠±3
x=±√3
x1=√3,x2=-√3