[tex]y = 3cos(x)[/tex]
Since we observe no vertical or horizontal shifts, we can say that:
[tex]y = acos(bx)[/tex]
Since the range of the function is multiplied by 3:
[tex] = > a = 3[/tex]
[tex]y = 3 \cos(bx) [/tex]
Since we observe a period of 2π for the function to repeat itself:
[tex]t = \frac{2\pi}{b} [/tex]
[tex]2\pi = \frac{2\pi}{b} [/tex]
[tex]b = \frac{2\pi}{2\pi} = 1[/tex]
[tex]y = 3cos(x)[/tex]
