MCQ
A quadratic equation $ax^2+ bx + c = 0,$ has coincident roots, if :
- A$ b^2-4 a c<0 $
- B$ b^2-4 a c>0 $
- ✓$ b^2-4 a c=0 $
- D$ b^2-a c=0 $
✓
Answer
Correct option: C.
$ b^2-4 a c=0 $
The roots of the quadratic equation $a x^2+b x+c=0$, In this formula the term $b^2-4 a c$ is called the discriminant.
If $b^2-4 a c=0$ so the equation has a single repeated root.
If $b^2-4 a c>0$, the equation has two real roots.
If $b^2-4 a c<0,$ the equation has two complex roots.
If $b^2-4 a c=0$ so the equation has a single repeated root.
If $b^2-4 a c>0$, the equation has two real roots.
If $b^2-4 a c<0,$ the equation has two complex roots.
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