The desert temperature,H, oscillates daily between 36ºF at 6am and 76ºF at 6pm. Write a possible formula forHin terms oft, measured in hours from 6am. Use the form

H=Acos(Bt) +C.

Ok, so I'm setting this up like this...

A = 20 (I subtracted 36 from 76 and divided it in half)

B = 1pi/6 (the number of hours, 12 hours between 6am and 6pm and then reduced it)

C = 36

I know these values are wrong, but i cant set this up correctly :( can anyone help me out?