If `f(y)=logy,` then `f(y)+f(1/y)` is equal to

A function f:R rarr R is defined by f(x+y)-kxy=f(x)+2y^2, AA xy in R and f(1)=2, f(2)=8 , where k is some constant, then f(x+y). (1/(x+y)) is equal to (where x+y ne y)

Let f be a function satisfying f(x+y)=f(x) *f(y) for all x,y, in R. If f (1) =3 then sum_(r=1)^(n) f (r) is equal to

Let f be a function satisfying f(x+y)=f(x) + f(y) for all x,y in R . If f (1)= k then f(n), n in N is equal to

Let f be a function satisfying f(x+y)=f(x) + f(y) for all x,y in R . If f (1)= k then f(n), n in N is equal to

Let f be a function satisfying f(x+y)=f(x) + f(y) for all x,y in R . If f (1)= k then f(n), n in N is equal to