Question

What do the graph of sine and cosine have common with the swinging you see

Answer 1

Answer with explanation:

The common property that holds with the swinging of the sine and cosine function graphs are:

• Both have the same maximum and minimum value (i.e. maximum value is 1 and minimum value is -1) and repeat in same pattern because of there period.
• Both have the same period as the graphs repeat after a fixed interval of time. ( as period of both the functions are 2π ).
• The graph of both the functions are smooth.

Answer 2

I imagine that the swinging you are describing is a swing going back and forth on a swing set.

This is the same pattern in the graphs of sine and cosine. They go back and forth between output values of -1 and 1.