Question

What is the midline equation of y = -9 cos(pi/2x -6) +8

Answer 1

Given a general cosine function as shown below

`y=a\cos (bx+c)+d`
`\begin{gathered} \text{where,} \\ d\Rightarrow\text{midline of the equation} \end{gathered}`

From the equation provided in the question

`\begin{gathered} y=-9\cos ((\pi)/(2)x-6)+8 \\ \end{gathered}`
`\begin{gathered} \text{comparing the general cosine formula with the cosine formula given, we have} \\ a=-9 \\ b=(\pi)/(2) \\ c=-6 \\ d=8 \end{gathered}`

Since the midline is d, then the midline equation will be

`y=8`

Hence, the midline equation is y = 8