JEE Main 20206 Sep, Morning shiftMathematicsMediumSets, Relations and Functions168× since 2002If f(x + y) = f(x)f(y) and ∑x=1∞f(x)=2\sum\limits_{x = 1}^\infty {f\left( x \right)} = 2x=1∑∞f(x)=2 , x, y ∈\in∈ N, where N is the set of all natural number, then the value of f(4)f(2){{f\left( 4 \right)} \over {f\left( 2 \right)}}f(2)f(4) is :AOption A. 23{2 \over 3}32BOption B. 19{1 \over 9}91COption C. 13{1 \over 3}31DOption D. 49{4 \over 9}94CheckSkip · show solution
