plotXpose is a companion app with the book Mathematics for Electrical Engineering and Computing by Mary Attenborough - click for more info

Tangent Mode

Home > Mode Menu > Tangent Mode

To display an approximate tangent line to the graph select this command from the Mode Menu. When in tangent mode clicking or tapping near any graph in the main window area results in a display of an approximate tangent to the graph. A message box also appears giving the following information: