This stack plots functions and finds their roots. To specify a function, type it into the field labeled f(x), and optionally set limits on the domain. Use the Change Scale or Shift View buttons if desired, and click Plot. To find a root of the function, first click Set Markers to specify two refernce points, one above and one below the x-axis. The markers can be dragged anywhere on the function to find other roots. Click Estimate to execute the root finding algorithm. It interpolates linearly between the markers to approximate the root. The estimated root and error in Y as well as the current marker positions are displayed. Successive clicks on Estimate decrease the error in most cases. Click on the title above to begin.