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Functions question

2021 · 25 Feb · Shift 2 · Q25

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PYQ Library
JEE Main
Mathematics
Functions
2021 · 25 Feb · Shift 2 · Q25

Functions question

2021 · 25 Feb · Shift 2 · Q25

JEE MainMathematicsFunctionsMCQ+4 / −1

A function f(x) is given by

f(x) = {{{5^x}} \over {{5^x} + 5}}

, then the sum of the series

f\left( {{1 \over {20}}} \right) + f\left( {{2 \over {20}}} \right) + f\left( {{3 \over {20}}} \right) + ....... + f\left( {{{39} \over {20}}} \right)

is equal to :

A
${{{39} \over 2}}$
B
${{{19} \over 2}}$
C
${{{49} \over 2}}$
D
${{{29} \over 2}}$

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