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gnitsuk

Member

Registered: 2006-02-09

Posts: 121

Partial Differential Equation Problem

Hi,

Could anyone please help me with the following?

This is question number 6 of Further Problems III on page 143 of K A Stroud's Further Engineering Mathematics.

given

and

and

prove that

Here's my attempt but I end up missing out the middle term of the answer. Can anyone see where I've gone wrong?

Starting with the generic formulae:

and

we have:

and

and

and

therefore

and

therefore

=

=

and similarly therefore

=

=

so now we subtract these two expressions to give

which simplifes to

=

which finally simplifies to

which is not the desired result, I am missing the

term.

So either the book is wrong, or I am wrong or the missing term evaluates to zero. I strongly suspect I am wrong. Can anyone help me see where I made a mistake?

Thanks,
Mitch.

gnitsuk

Member

Registered: 2006-02-09

Posts: 121

Re: Partial Differential Equation Problem

No worries,

Found the problem.

Thanks,
Mitch.