求一个一元二次方程配方法过程 3X눀+4X-1=0

2024-12-16 13:32:34
推荐回答(2个)
回答1:

解:3X²+4X-1=0
X²+(4/3)X-(1/3)=0
x²+4/3×+(4/3*1/2)^2-(4/3*1/2)^2-1/3=0
(x+4/3*1/2)^2-(4/3*1/2)^2-1/3=0
(x+2/3)^2-4/9-1/3=0
(x+2/3)^2=7/9
x+2/3=±√7/3
x=±√7/3-2/3
X1=√7-2/3
X2=-√7-2/3

回答2:

解:3X²+4X-1=0
X²+(4/3)X-(1/3)=0
X²+(4/3)X=1/3
X²+(4/3)X+(2/3)²=(1/3)+(2/3)²
[X+(2/3)]²=7/9
X+(2/3)=±(1/3)√7
X=-(2/3)±(1/3)√7
X1=(1/3)(-2+√7)
X2=(1/3)(-2-√7)