The asymptote of the function f(x)=3^x+1-2 is a. y= -2 b. y= -1 c. y=1 d. y= 2 it’s y-intercept is a. (0,-2) b. (0,-3) c. (0,1) d. (0,-1)

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) = .