配方法求5x=3x²-1
问题描述:
配方法求5x=3x²-1
答
3x²-5x=1
x²-5x/3=1/3
x²-5x/3+25/36=1/3+25/36=37/36
(x-5/6)²=(±√37/6)²
x-5/6=±√37/6
x=5/6±√37/6
x=(5-√37)/6,x=(5+√37)/6