Answer:
Step-by-step explanation:
Alright, lets get started.
The amplitude is given as 4 means a is 4
Period is given as [tex]\frac{\pi }{2}[/tex] means
[tex]\frac{2\pi }{b}=\frac{\pi}{2}[/tex]
Cross multiply
[tex]b=4[/tex]
Cos function will be [tex]y=4cos(4x)[/tex]
Please refer the diagram I have attached.
