Do I have this one correct
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Answer:
Option B is correct
Step-by-step explanation:
Given is a cos funciton.
Period = 3
Max = 20 and minimum =0
Hence centre line is y = 1/2 (max+min)
i.e. y =10 is the central line
Let the funciton be of the form
y = a cos (bx+C)+d
We got d = 10...i
Period =3
Hence b = [tex]\frac{2\pi}{3}[/tex] ... ii
Amplitude = a = distance of max from central line = 20-10 =10...iii
Since reflection over x axis, sign of a =negative
a=-10
Since no horizontal shift, c=0 ... iv
Put to gether the function is
[tex]y=-10cos\frac{2\pi x}{3} +10[/tex]