Great question. The answer to this is yes. You can. However, the vector will be a vector of unitless values that will not have direction or magnitude. A vector can be described by having a direction and magnitude but exponents of e must be unitless. You can have e^(vector*variable) where that vector has a direction and magnitude, however. But vector*variable will then be unitless. Hopefully this sufficiently answers your question. Best wishes. -Corey