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Discriminant of a Quadratic

Discriminant of a Quadratic

The number D = b2 – 4ac determined from the coefficients of the equation ax2 + bx + c = 0. The discriminant reveals what type of roots the equation has.

Note: b2 – 4ac comes from the quadratic formula.

 

Table showing Discriminant D=b²–4ac values and their corresponding roots: D<0 complex conjugates, D=0 one real zero, D>0 two...

 

 

See also

Quadratic equation, complex conjugate, multiplicity, real number, perfect square, rational number