Question

Plz help me with this

Answer 1

Answer: A) y = -5 cos(2x - π)

Explanation:

`\text{The standard form of a cosine equation is: y=A sin(Bx - C) + D}\\\\\bullet\text{A = amplitude}\\\\\bullet\text{Period = }(2\pi)/(B)\\\\\bullet\text{Phase Shift = }(C)/(B)\\\\\bullet\text{D = vertical shift (up if positive, down if negative)}`

In the given graph,

• A (amplitude) = 5
• Phase Shift
  `\bigg((C)/(B)\bigg) = (\pi)/(2)` to the right
• P (period) = π --> B = 2
• D (vertical shift) = 0
• There is also a reflection across the x-axis.

`\implies \large\boxed{y = -5cos(2x-\pi)}`

see graph below for verification