MCQ
If $ax^2+ bx + c = 0$ has equal roots, then $c$ is equal to :
- A$-\frac{\text{b}^2}{\text{2a}}$
- B$-\frac{\text{b}^2}{\text{4a}}$
- C$\frac{\text{b}^2}{\text{4a}}$
- ✓$\frac{\text{b}^2}{\text{4a}}$
✓
Answer
Correct option: D.
$\frac{\text{b}^2}{\text{4a}}$
If $ax^2+ bx + c = 0$ has equal roots,
then $b^2- 4ac = 0$
$\Rightarrow 4ac = b^2$
$\Rightarrow\text{c} = \frac{\text{b}^2}{\text{4a}}$
then $b^2- 4ac = 0$
$\Rightarrow 4ac = b^2$
$\Rightarrow\text{c} = \frac{\text{b}^2}{\text{4a}}$
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