Mrs. Hanely's geometry class is trying to approximate the height of
the Washington Monument. They notice that the monument casts a
333-foot-long shadow at the same time that a 5-foot-tall student casts
a 3-foot-long shadow. Approximate the height of the Washington monument?

Determine the volume of a cylinder bucket if the diameter is 8.5 in. and the height is 11.5 in.

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) = .

In triangle abc, angle c is a right angle. find the value of the trig function indicated. find tan a if c = 17 and a = 8