Fundamentals of Scientific Research for Doctor of Economics and Management [16] The formula for the solution of a quadratic function of one variable

1. The form of a quadratic function of one variable

2. Graphs and properties of quadratic functions of one variable

The image of a quadratic function is a parabola. The fixed-point formula of the image is (-b/2a, 4ac-b*b/4a), and the symmetry axis straight line x=-b/2a.

3. Mokune formula

For a quadratic equation of the form ax*x+b*x+c=0, its root formula is:

 4. Vedic Theorem

If x1 and x2 are the two roots of the equation ax*x+b*x+c=0, then

x1+x2=-b/a,

x1*x2=c/a，

|x1-x2|=△/|a|