Respuesta :

Answer:

Step-by-step explanation:

a  is just the peak value which looks like  a = 2.5

this cos wave function has a phase shift of 60°    A normal cos function with no phase shift has a b of zero

so to make this cos function to have NO phase shift we would substract 60° then cos 0 would be 1×a  so b = -60°

y = 2.5cos(x-60)     when x =60    cos(60-60) = 1     y = 2.5×1

The second question is odd but i'll try

   y = f(2x)      (4, 10)       the origianl f(x) was (4, 5)

   y = f(x) - 7    (4, -2)