Let f:R→R, be defined as f(x)=ex2+cosx, then f is
one-one and onto
one-one and into
many-one and onto
many-one and into
fx = ex2+cos x is even function , so it is not one-one i.e many one
also fx is not onto since ex2≥1 ⇒ex2+cosx >0
Range of fx is 0,∞ which is not equal to codomain R hence f is into