y = Acos(Bx) + D;
D = 4, A = 2. Now T = 2π/B = 5π/8, B = 2π/(5π/8) = 16/5
WE get y = 2cos(16/5x) + 4
Answer:
and 
Step-by-step explanation:
Recall that
is a value of the function cosine for the special angles:
and
, then:

Answer:
a and b
Step-by-step explanation:
i think b i know a for sho
Check the picture below.
bearing in mind that twin sides stemming from a common vertex, will make twin angles at the base, thus 74° has a twin.