Quadratic Equation

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• Solver : Computing the Discriminant by jim_thompson5910(8191)  

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	ax2+bx+c = 0, 

You can think about a quadratic equation in terms of a graph of a quadratic function, which is called a parabola. The equation means that you have to find the points on the horizontal axis (x) where the graph intersects with the axis.

To solve a quadratic equation, you have to calculate a number called discriminant, usually denoted as d:

d = b2-4ac

Depending on the value of d, there are the folowing three possibilities:

1. Discriminant d is greater than zero. The equation has two solutions.

   x1,2 = -b ± sqrt( b2-4ac )
          ------------------
                  2a
   
   

2. Discriminant is zero. There is only one solution.

   x = -b/2a
   

3. Discriminant is less than zero. No solutions are defined.

   Note: for those of you who study complex numbers, there is a complex solution. If you do not know what complex numbers are, skip this part.

	(x+q)2-p

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