Let f : R → R and g : R → R be defined as
\(\rm f(x) = \left\{\begin{matrix} \rm log_ex, & x > 0 \\[0.3em] \rm e^{-x}, & x \leq 0 \\[0.3em] \end{matrix}\right.\) and
\(\rm g(x) = \left\{\begin{matrix} \rm x, & \rm x \geq 0 \\[0.3em] \rm e^{x}, & \rm x < 0 \\[0.3em] \end{matrix}\right.\). Then gof : R → R is :
1
one-one but not onto
2
neither one-one nor onto
3
onto but not one-one
4
both one-one and onto