(A) f is one-one onto            (B) f is many-one onto

(C) f is one-one but not onto (D) f is neither one-one nor onto.

solution:

f : R → R be characterized as f(x) = 3x let x and y has a place with R to such an extent that f(x) = f(y) 3x = 3y or x = y

f is one-one capacity. Presently, y = f(x) = 3x

Or on the other hand x = y/3

f(x) = f(y/3) = y

In this way, f is onto work. Alternative (A) is right.