WBJEE · Maths · Application of Derivatives
Let \(f(x)\) be a second degree polynomial. If \(f(1)=f(-1)\) and \(p, q, r\) are in A.P., then \(f^{\prime}(p), f^{\prime}(q), f^{\prime}(r)\) are
- A in A.P.
- B in G.P.
- C in H.P.
- D neither in A.P. or G.P. or H.P.
Answer & Solution
Correct Answer
(A) in A.P.
Step-by-step Solution
Detailed explanation
\(\begin{aligned} & f(-1)=f(1) \Rightarrow b=0 \\ & f(x)=a x^2+c \quad \Rightarrow f^{\prime}(x)=2 a x\end{aligned}\)
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