JEE MATHEMATICS MCQ: FUNCTIONS

1 Easy

1 of 1

Analyzing +4 | -1

Let

f(x)=9^x /\left(9^x+3\right)

for all

x \in \mathbb{R}

. Then the value of

\sum_{r=1}^{2008} f(r / 2009)

View answer and explanation

Correct option: A

1004

The correct answer is A (1004) because the sum can be simplified by pairing terms

f(x)

and

f(1-x)

, which sum to 1, and then summing these pairs.

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