# VC3.26

From Example Problems

Here --(1)

Since a is a constant vector, --(2)

From (1), --(3)

Now, by definition of curl --(4)

But

=

= by (3)

= by (2),(3)

Therefore,

=

=

= --(5)

Let so that etc. --(6)

Also --(7)

Using (6) and (7),(5)reduces to

=

=

=

=

= --(8)

But

and

Therefore

= by (8)

or by (4)

Hence the required is proved.