Mathematics · 2021
JEE Main · 4 August 2021, Shift 2 · Q67
Let f: R → R be twice differentiable and satisfy f(x+y)=f(x)+f(y). If f^′(0)=1, then which of the following is true?
Let $\displaystyle f: \mathbb{R} \rightarrow \mathbb{R}$ be twice differentiable and satisfy $\displaystyle f(x+y)=f(x)+f(y)$. If $\displaystyle f^{\prime}(0)=1$, then which of the following is true?
Official answer
(2)
$\displaystyle f^{\prime}(2)=1$
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