MCQ
If $f(x)=a x^2+b x+c$ has no real zeros and $a + b + c < 0,$ then :
- ✓$C < 0$
- BNone of these
- C$C = 0$
- D$C > 0$
✓
Answer
Correct option: A.
$C < 0$
We are given $a + b + c < 0$
$\Rightarrow \text{f}(1) < 0$
So, $f(x)$ must be negative for all $x$.
$\Rightarrow \text{f}(1) < 0$
So, $f(x)$ must be negative for all $x$.
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