Hi, I wasn't too sure what category to put this in, so i'm sorry if pre-calculus is wrong.

I came across this question but can't seem to prove it:

If , show that:

(i) , for

(ii) ,

My workings:

(i)

After this I couldn't find a way to prove it and I just kept going round in circles.

(ii)

... from part one

Which I don't think's possible.

Any help here would be appreciated.

Thanks.