Answer: A) y = -5 cos(2x - π)
Step-by-step explanation:
[tex]\text{The standard form of a cosine equation is: y=A sin(Bx - C) + D}\\\\\bullet\text{A = amplitude}\\\\\bullet\text{Period = }\dfrac{2\pi}{B}\\\\\bullet\text{Phase Shift = }\dfrac{C}{B}\\\\\bullet\text{D = vertical shift (up if positive, down if negative)}[/tex]
In the given graph,
- A (amplitude) = 5
- Phase Shift [tex]\bigg(\dfrac{C}{B}\bigg) = \dfrac{\pi}{2}[/tex] to the right
- P (period) = π --> B = 2
- D (vertical shift) = 0
- There is also a reflection across the x-axis.
[tex]\implies \large\boxed{y = -5cos(2x-\pi)}[/tex]
see graph below for verification
