WBJEE · Maths · Quadratic Equation
The expression \(a x^{2}+b x+c(a, b\) and \(c\) are real \()\) has the same sign as that of a for all \(x\) if
- A \(b^{2}-4 a c>0\)
- B \(b^{2}-4 a c \neq 0\)
- C \(b^{2}-4 a c \leq 0\)
- D \(\mathrm{b}\) and \(\mathrm{c}\) have the same sign as that of \(\mathrm{a}\)
Answer & Solution
Correct Answer
(C) \(b^{2}-4 a c \leq 0\)
Step-by-step Solution
Detailed explanation
Hint: C-l: If \(a>0, a x^{2}+b x+c>0, b^{2}-4 a c < 0, \quad C-I I:\) If \(a \leq 0, a x^{2}+b x+c \leq 0, D \leq 0\)
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