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**Nemesis10192** Of course not; functions map a range of inputs to a range of outputs, so therefore require at least a single variable to do so. So for instance e^x is a function that maps x to e^x. e^5 is not a function, it always has constant value. Ln(7x) is a function, but ln(7) is not. The derivative (wrt to x) of e^(ln7x) is as has been pointed out, 7, but the derivate of e^((ln7)x) is ln(7)e^((ln7)x) since it is of the form e^kx where k=ln7 so you can see it does indeed follow normal differentiation laws.