If f(x)f(y)=f(x+y) for all x,y, suppose f(5)=2 and f1(0)=3,  then f(5) is equal to

f(x+y)=f(x)f(y)⇒             f(0+5)  = f(0)f(5)     ⇒   f(0)=1          ∴f(5)=2≠0Also,       f(5)=limh→0f(5+h)−f(5+0)h                                      =limh→0f(5)f(h)−f(5)f(0)h                              = f(5)limh→0f(h)−f(0)h                             = f(5)f1(0)=2×3=6Hence (1)is the correct answer.