## anonymous 3 years ago Help

1. anonymous

huh?

2. abb0t

Is this a medical emergency? If so, please call your local emergency number.

3. anonymous

it's math emergency

4. anonymous

wats ur question?

5. anonymous

These are the pictures that I've uploaded for my question

6. anonymous

oh glob, sorry i cant help, thats too hard, bye. :)

7. abb0t

I vaguely remember doing this, but I think you want to use the exponential form of cosh and sinh to prove it.

8. anonymous

Yeah, noob google series expansion of hyperbolic cosine and sine

9. anonymous

So sin z is equal to some summation. You multiply it by i. Work out a few terms in the summation making sure to remember that i^2=-1 and try to simplify it to look like the sinh z formula.

10. anonymous

11. anonymous

For -1 < p < 1 prove that $\sum_{n=0 }^{\infty} p^{n}\cos nx =\frac{ 1= pcos x }{ 1-2pcosx + p^2 }$

12. anonymous

bleh too much effort