Final answer:
The exponential function y=e^x does not have a vertical asymptote because as x approaches negative infinity, y approaches 0, but never actually reaches it.
Step-by-step explanation:
To determine the vertical asymptote of the exponential function y=ex, we need to understand what vertical asymptotes represent.
A vertical asymptote is a line that the graph of a function approaches but never touches as the independent variable (in this case, x) approaches a specific value.
For the claimed function, y=ex, its graph is continuously rising as x increases and approaches 0 as x approaches negative infinity but never actually reaches 0. This behavior means that unlike the function y=1/x, which has a vertical asymptote at x=0, the exponential function y=ex does not have a vertical asymptote at any finite value of x.