WBJEE · Maths · Functions
\(f(x)\) is real valued function such that \(2 f(x)+3 f(-x)=15-4 x\) for all \(x \in R\). Then \(f(2)=\)
- A \(-15\)
- B 22
- C 11
- D 0
Answer & Solution
Correct Answer
(C) 11
Step-by-step Solution
Detailed explanation
\(2 f(x)+3 f(-x)=15-4 x\)...(1) Replace \(x\) by \(-x\) \(2 f(-x)+3 f(x)=15+4 x\) ...(2) After solving (1) and (2), we get \(\begin{array}{l} f(x)=4 x+3 \\ \therefore f(2)=8+3=11 \end{array}\)
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