Mathematics · 2025
JEE Main · 28 January 2025, Shift 1 · Q2
If f(x)=2^x/(2^x+√ 2), x ∈ R, then Σ_k =1^81 f(k/82) is equal to
If $\displaystyle f(x)=\frac{2^x}{2^x+\sqrt{2}}, \mathrm{x} \in \mathbb{R}$, then $\displaystyle \sum_{\mathrm{k}=1}^{81} f\left(\frac{\mathrm{k}}{82}\right)$ is equal to
Official answer
From NTA’s final answer key for this paper.
(1)
$\displaystyle \frac{81}{2}$
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.