Given the function:
![f(x)=2cos(3x-(5\pi)/(6))-2](https://img.qammunity.org/2023/formulas/mathematics/college/n6yv8u3ttdme8s9wc2fobe7zoy4dqhseih.png)
You need to remember that the General Equation of the Cosine Function is:
![y=Acos(B(x+C))+D](https://img.qammunity.org/2023/formulas/mathematics/college/bkyufhtdzf8k5fvupznja3c4djpd7ne3s2.png)
Where:
- The Amplitude is:
![|A|](https://img.qammunity.org/2023/formulas/mathematics/college/mil9yi92xsju1fdsv72ouptt9xuxn80hvz.png)
- The Period is:
![(2\pi)/(B)](https://img.qammunity.org/2023/formulas/physics/college/6kecy9rvg280c84x7xmng8be0hti1ywz42.png)
- The horizontal shift is "C".
- The Vertical Shift is "D".
- The midlline is:
![y=D](https://img.qammunity.org/2023/formulas/mathematics/college/4zc041jqx09u7nel5mr68i5rk13hl08j2k.png)
In this case, you can identify that:
![D=-2](https://img.qammunity.org/2023/formulas/mathematics/college/ne8flza2ptj11mo314xxpui34nymql9c5n.png)
Therefore, the midline is: