The above pictures were taken from a video that the yellow shape is moving from left to right and drawing a triangle by moving at the same time.

Please type a paragraph to explain:

-The main question is what is application? that includes:

- How and where the triangle come from?

- What is the mathematical equation for this? (what is happening?)

- What is the name of this tool?

The answer can be related to Autotuting, wave (static or top of the other one), voltage or...

Here is a example:

Area under fotot) f(t) 081 05