7. What is the sin(90-x)? A. 0.3
B. 0.6
C. 0.9
D. 0.4
E. 0.2
F. 0.5

after trying it my self I got .2 but I'm not sure

Which of the following tables represents exponential functions?

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) = .

Are the corresponding angles congruent? explain why or why not.