Mathematics · 2021
JEE Main · 25 February 2021, Shift 2 · Q65
A function f(x) is given by f(x)=5^x/(5^x+5), then the sum of the series f(1/20)+f(2/20)+f(3/20)+… …+f(39/20) is equal to:
A function $\displaystyle f(x)$ is given by $\displaystyle f(x)=\frac{5^x}{5^x+5}$, then the sum of the series
$$f\left(\frac{1}{20}\right)+f\left(\frac{2}{20}\right)+f\left(\frac{3}{20}\right)+\ldots \ldots+f\left(\frac{39}{20}\right)
$$
is equal to :
Official answer
(3)
$\displaystyle \frac{39}{2}$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.