A set that is not convex is called a non-convex set. A polygon that is not a convex polygon is sometimes called a concave polygon, and some sources more generally use the term concave set to mean a non-convex set, but most authorities prohibit this usage.
In either case you don't need to deal with the absolute value. A rectified sine wave is a periodic signal with a period equal to half of the full sinusoid, I would write the sine in exponential form and integrate over one period to find the series coefficients.
It is also clear by the graph that 2p is the smallest number for which this is true. The period of sin(x) is 2Ï. The amplitude of a sinusoidal wave is the distance from the central axis (the x-axis in this case) and the maximum or minimum value of the wave.The phase shift of a curve is the shift, left or right, of the base curve.t is also clear by the graph that 2p is the smallest number for which this is true. The period of sin(x) is 2Ï. The amplitude of a sinusoidal wave is the distance from the central axis (the x-axis in this case) and the maximum or minimum value of the wave.