JEE MATHEMATICS MCQ: FUNCTIONS

1 Easy

1 of 1

Analyzing +4 | -1

f(x + y) = f(x)f(y)

and

\sum\limits_{x = 1}^\infty {f(x) = 2,x,y \in N},

where N is the set of all natural numbers, then the value of

\frac{{f(4)}}{{f(2)}}

View answer and explanation

Correct option: D

\frac{4}{9}

Option D is correct because by using the given functional relation and the sum, we find f(x) = (2/3)^x, and thus f(4)/f(2) = 4/9.

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