Laplace Transform of Bessel Function of the First Kind of Order One

From ProofWiki
Jump to navigation Jump to search

Theorem

Let $J_1$ denote the Bessel function of the first kind of order $1$.


Then the Laplace transform of $J_1$ is given as:

$\laptrans {\map {J_1} t} = \dfrac {\sqrt {s^2 + 1} - s} {\sqrt {s^2 + 1} }$


Proof

\(\ds \map {J_0'} t\) \(=\) \(\ds -\map {J_1} t\) Derivative of $x^n$ by Bessel Function of the First Kind of Order $n$ of $x$
\(\ds \leadsto \ \ \) \(\ds \laptrans {\map {J_1} t}\) \(=\) \(\ds -\laptrans {\map {J_0'} t}\)
\(\ds \) \(=\) \(\ds -\paren {s \laptrans {\map {J_0} t} - \map {J_0} 0}\) Laplace Transform of Derivative
\(\ds \) \(=\) \(\ds -\paren {s \laptrans {\map {J_0} t} - 1}\) Bessel Function of the First Kind of Order Zero
\(\ds \) \(=\) \(\ds 1 - s \dfrac 1 {\sqrt {s^2 + 1} }\) Laplace Transform of Bessel Function of the First Kind of Order Zero
\(\ds \) \(=\) \(\ds \dfrac {\sqrt {s^2 + 1} - s} {\sqrt {s^2 + 1} }\) rearranging

$\blacksquare$


Sources