Step 1
The period of a sinusoid is the length of a complete cycle. For basic sine and cosine functions, the period is 2π.
The Period goes from one peak to the next (or from any point to the next matching point)
Step 2
From the graph of the function, the period or one complete cycle can be traced from (0,-2) where the functions crosses the y-axis up to (6,-2) where it is at the same y coordinate point as before.
Hence, the period=6
