Donna and phyllis are reviewing for a math final. they have 150 pages to cover. donna can review 37 pages an hour, but phyllis can only go
2
3
as fast as donna. about how long does it take each girl to finish?

Graph the system: f(x)= 3/x-2; f(x)= 1/2x + 2

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) = .

Which linear inequality is represented by the graph?