Hi all ----

I actually get part (ii) of this question - but I'm just curious - how can I formally prove the symmetry? The question doesn't ask this but I'm just curious. The green box is the solution.

Part (ii) ---I can see that reaches maximum when .

But it also looks like is symmetric about . How would I prove this?

I know how to do this for ---

is symmetric about because so .

Thanks a lot ---