Which could be the area of one face of the rectangular prism? Select three options.

A rectangular prism with a length of 11 centimeters, width of 4 centimeters, and height of 6 centimeters.

20 centimeters squared
24 centimeters squared
44 centimeters squared
48 centimeters squared
66 centimeters squared

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) = .