Awindow is shaped like a semicircle with a diameter of 5.2 feet. what is the area of the window? round to the nearest tenth.

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) = .

Yesterday, george drank 1 small bottle and 2 large bottles, for a total of 1,372 grams. the day before , he drank 1 small bottle and 1 large bottle, for the total of 858 grams. how many grams does each bottle hold?

*segment an is an altitude of right ? abc with a right angle at a. if ab = 2root 5 in and nc = 1 in, find bn, an, ac.