一元二次方程例题解法大家教教我,我要例题,现在先不给分,要是答案好,
来源:学生作业帮 编辑:搜狗做题网作业帮 分类:数学作业 时间:2024/08/08 21:16:34
一元二次方程例题解法
大家教教我,我要例题,现在先不给分,要是答案好,
大家教教我,我要例题,现在先不给分,要是答案好,
![一元二次方程例题解法大家教教我,我要例题,现在先不给分,要是答案好,](/uploads/image/z/6576478-70-8.jpg?t=%E4%B8%80%E5%85%83%E4%BA%8C%E6%AC%A1%E6%96%B9%E7%A8%8B%E4%BE%8B%E9%A2%98%E8%A7%A3%E6%B3%95%E5%A4%A7%E5%AE%B6%E6%95%99%E6%95%99%E6%88%91%2C%E6%88%91%E8%A6%81%E4%BE%8B%E9%A2%98%2C%E7%8E%B0%E5%9C%A8%E5%85%88%E4%B8%8D%E7%BB%99%E5%88%86%2C%E8%A6%81%E6%98%AF%E7%AD%94%E6%A1%88%E5%A5%BD%2C)
ax²+bx+c=0(a≠0)
x²+(b/a)x+c/a=0,x²+(b/a)x+(b/2a)²-(b/2a)²+c/a=0,
(x+b/2a)²-b²/4a²+c/a=0,(x+b/2a)²-(b²-4ac)/4a²=0,
(x+b/2a)²=(b²-4ac)/4a²,当b²-4ac≥0时有解,
(x+b/2a)=±[√(b²-4ac)]/2a,
x=-b/2a±[√(b²-4ac)]/2a,
x=[-b±√(b²-4ac)]/2a,
x1=[-b+√(b²-4ac)]/2a,
x2==[-b-√(b²-4ac)]/2a,
x²+(b/a)x+c/a=0,x²+(b/a)x+(b/2a)²-(b/2a)²+c/a=0,
(x+b/2a)²-b²/4a²+c/a=0,(x+b/2a)²-(b²-4ac)/4a²=0,
(x+b/2a)²=(b²-4ac)/4a²,当b²-4ac≥0时有解,
(x+b/2a)=±[√(b²-4ac)]/2a,
x=-b/2a±[√(b²-4ac)]/2a,
x=[-b±√(b²-4ac)]/2a,
x1=[-b+√(b²-4ac)]/2a,
x2==[-b-√(b²-4ac)]/2a,