I've already solved this problem, but the assessment system I'm supposed to insert my answer to keeps telling me it's incorrect, so I must have made a mistake somewhere and can't spot it.

So I'll write out, step by step, what I've done:

Right Hand Side:

Left Hand Side:

Rewriting LHS using partial fractions:

Let

Let

So then I get LHS to be:

Integrating the LHS with respect to y gives

So now I have

But apparently that's the wrong answer and I can't, for the life of me, figure out where I'm going wrong.