Instructions

  1. Move the black points to change the length of segments.
  2. Observe the diagram for different values of \(a\) and \(b\) (and \(c\), in case it exists).
  3. Figure out the identity.
  4. The apps contain tips to help find the identities. To see them, move from left to right the corresponding point.
  5. To check your solution, move from left to right the corresponding point.

Remark: After dragging a point from a slider, you may find yourself not able to deselect it. If such a situation occurs (which should be sporadic), just double click on the selected point.