What is the equation of B
d, simplified?

If a and b are the measures of two first quadrant angles and sin a = 4/9 and sin b = 2/5 find sin(a+b).

Choosing a booth location: your manager is sending two people to work at the conference. she wants a booth that will give your company good visibility for no more than 35% of the total budget ($3000). the conference coordinator just told you there are only five booths left. which booth will you choose? write the inequality that shows how much money you can spend on the booth simplify the inequality that shows how much money you can spend on the booth.

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) = .