$ b=e $

$ \lim_{h \to 0} \frac{b^h-1}{h} $

$ \lim_{h \to 0} \frac{e^h-1}{h}=1 $

mys(b, h) = (b^(h) - 1) / h
a(b, h) = (b^(h) - 1) / h
A = (2, 2)
B = (2.56, 1.16)
u = Vector(A, B)