x*x-x-1不等于0,求x不等于几?
问题描述:
x*x-x-1不等于0,求x不等于几?
答
x²-x≠1
x²-x+1/4≠1+1/4
(x-1/2)²≠5/4
x-1/2≠±√5/2
x≠(1-√5)/2且x≠(1+√5)/2