#### ThermalRunaway

##### New Member

x1 = sin (2pi . 1 . nts) // 1 Hz sinusoid of peak amplitude 1

x2 = sin (2pi . 3 . nts) // 3 Hz sinusoid of peak amplitude 1

I have been investigating the theoretical output from a system that adheres to the following equation:

y = x_squared

when I apply the addition of x1+x2 to it.

I have proven that the system is non-linear because the theoretical output is a bunch of components that were not present in the original signals, as follows:

0Hz @ amplitude 1

2Hz @ amplitude 0.5

4Hz @ amplitude -1

6Hz @ amplitude -0.5

I calculated these with the help of trigonometric identities (and a text book )

I understand all of this, but... what about the 0Hz component? What does this look like in practice? Would it be seen as a D.C. level?

Brian