(a)
\The Bessel function of order
is
and its value at
is
.
The Bessel function satisfies the differential equation
.
Therefore,
.
Substitute
in above expression.

(b)
\Consider the Bessel function
.
Differentiate on each side with respect to
.


Substitute
in above expression.

Substitute
in above expression.

.
(a)
.
(b)
.