The discriminant is the part of the quadratic formula underneath the square root symbol:

D = b²-4ac

You need to plug in the values for 'a', 'b' and 'c' for a given quadratic equation: ax^2 + bx + c = 0

Then use the solver to do the calculation.

For example, for the quadratic equation:

2x^2 + 3x - 1 = 0

a = 2, b = 3, c = -1 and the discriminant is equal to:

D = 3^2 - 4*2*(-1)

........

Click here to see the calculation

........

D = 17