Can someone please help me with IX and X. I would so appreciate it please.

Prove (a) cosh2(x) − sinh2(x) = 1 and (b) 1 − tanh 2(x) = sech 2(x). solution (a) cosh2(x) − sinh2(x) = ex + e−x 2 2 − 2 = e2x + 2 + e−2x 4 − = 4 = . (b) we start with the identity proved in part (a): cosh2(x) − sinh2(x) = 1. if we divide both sides by cosh2(x), we get 1 − sinh2(x) cosh2(x) = 1 or 1 − tanh 2(x) = .

At a book fair, joe bought 24 books at 3 for $5 and had $2 left. how much money did he have at first?

What value of s iwhat value of s is a solution to this equation? 27+6s=9ss a solution to this equation? 27+6s=9s