bobbym wrote:

Hi BarandaMan;

I am sorry but I can not see that. It is showing up very dark on my browser.

I have so far:

that is all I can make out.

Thank you! You are right so far!! The end is -1/yLi^y

I have differentiated with respect to Li correctly. The correct answer when differentiating with respect to Pi is on the sheet (let me know if you cannot see it). I cannot do it though, wrt Li I can do though!!

Yes exactly, the little y is meant to be gamma so treated differently from the big Y!

I can do the fourth term as the Pi just dissappears right?

I have no idea how to use the chain rule here when there are fractions and powers like that, I've never seen a function like this before. Please can you help?

bobbym wrote:

Hi;

If you mean this term

Simplify it to:

Thank you bobby, how/why does that rule work?

So Pi^-n * Pi = Pi^1-n? (With the divided by P excluded). Why does that work? How? Is this always the case?
Thanks

Ok thank you for all your help bobby. I really cannot do this.

If anyone is willing to post a solution to the differentiation with respect to Pi, please let me know and explain. It may seem like I am not making an effort but I have, a lot, and me posting my working on here will be really unhelpful.

bobbym wrote:

Hi;

I can post a solution but I think you need some help with applying the power rule. We can go over it term by term...

This is the derivative with respect to Pi.

Thanks. I have tried for days to work this out but I still do not understand this at all. Also, the P^2 on the bottom is inconsistent with the answer from the book. We want to differentiate only with respect to the Pi, not with respect to the 'P' on the bottom....this is completely different to the answer? Now I have two things I don't understand

bobbym wrote:

Hi;

For the next term let's simplify it a bit before differentiating

Is that clear to start?

Yes! Thank you! That all makes sense, except for the last line, I don't know where the divided 'P' has gone?

Hi;

When you have an expression like:

Can someone just please explain why (Pi/P)^-n / P gives P^1-n... please  someone?

Hi;

please someone this isn't even the question I wanted to solve in the first place and now I am stuck just simplifying things

Simplifying is supposed to make things easier, it is part of math. Without it some problems are impossible.

It's taking me 5 days to do one question Maths is so difficult and I try so hard.

Pardon me for saying but you come in for 30 seconds and then I do not see you for 2 days. 5 x 30 seconds is 2 and half minutes of time spent on this problem. I could not solve it that quickly either. In order to get something out of this you have to spend the time in here with me, asking questions.

Hi;

Hi;

Can you differentiate this wrt Pi?