When you multiply by , the result is (in the last line). The rest is correct.
I have an equation I need to differentiate but I'm not sure where I'm going wrong.
I've uploaded a copy of the question with my working as it's a bit easier as opposed to typing it all out.
The question itself (it's cut off slightly on the pic) is...
If someone could give me a tip where I'm going wrong, that would be appreciated..