I'm new to this type of question and I can only get so far into the question before I don't know what to do - I haven't been taught more but I very much would like to know.

It asks:

Use the substitution = to show that

= where the values of a, b and k are to be found.

Hence evaluate .

So far I can say that = and =

=

=

=

=

And this is as far as I can get.

Could someone please help me finish the question and understand how it works from this point onwards?

Any help is greatly appreciated