The Binomial Theorem proof by exponentials
Fractional Calculus of Zero
Disproving D^{1/2}e^x=e^x with explanation
The following picture is showing graphically the relation between e^x expansion terms and Reciprocal gamma function.
The plot is for x=1,x=2,x=3
Also it shows the differentiation and integration manner of e^x.
Click on the image to enlarge it
So if we move the terms of e^x half step to the direction of differentiation, we will get the terms of half-integers order differentiation.
D_x^{1/2}(e^x)=\cdots +\frac{x^{-3/2}}{(-3/2)!}+\frac{x^{-1/2}}{(-1/2)!}+\frac{x^{1/2}}{(1/2)!}+\frac{x^{3/2}}{(3/2)!}+\cdots
(Note that when I use non-integer factorials (a)! I am indeed referring to Gamma function)
Now the question which I am trying to answer is:
"Does this series converges? and how to deal with it in case of it diverges?"
I will use e_{\alpha}^x as annotation for D_x^{\alpha}(e^x)
I recently proved this nice relation where a,b \in \Bbb R
e^a\cdot e_{\alpha}^b=e_{\alpha}^{a+b} \tag1
Which I can prove it by using the binomial formula from the previous post
\frac{(a+b)^{\alpha}}{\alpha!}=\sum_{k \in \Bbb Z} \frac{a^k}{k!} \cdot \frac{b^{\alpha-k}}{(\alpha-k)!}
And I already proved ,in the previous post, that the binomial theorem is actually a term of two multiplied exponential function (\alpha can be any real number).
By using eq(1) let us now test the relation for \alpha=\frac12
For a=0 we have,
e^0\cdot e_{1/2}^b=e_{1/2}^{0+b} \Rightarrow e_{1/2}^b=e_{1/2}^b
and that is a logical result.
For b=0 we have,
e^a\cdot e_{1/2}^0=e_{1/2}^{a+0} \Rightarrow e^a \cdot e_{1/2}^0=e_{1/2}^a
We all know that e_{1/2}^0=\infty
Hence e_{1/2}^a=\infty \cdot e^a
Therefore the expansion series of e_{1/2}^a is not well-defined, but actually if we look to fractional calculus of 'zero number' which I studied it before in an earlier post makes the whole fractional calculus undefined and for that reason we always set the zero fractional calculus value to zero.
Thus we always have to eliminate the expansion series terms of e_{1/2}^a that met the half-order differentiation of zero expansion so that it finally converges.
D_x^{1/2}(e^x)=\frac{x^{-1/2}}{(-1/2)!}+\frac{x^{1/2}}{(1/2)!}+\frac{x^{3/2}}{(3/2)!}+\frac{x^{5/2}}{(5/2)!}+\cdots
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