Keys: press [ or ] to pick the point at a or the other end. Press ← or → to move it one step. Hold Shift with an arrow key to move it five steps. Press Esc to let go. Press + or − to zoom.
Function
Write it as in R: 50*x^-0.4 or 781.9*exp(0.1216*(Week - 25)). A makeFun line works too.
Interval
Scroll or pinch to zoom. Drag the background to pan.
Average rate of change
Shrinking intervals
The stopping test is met when both sides round to the same value at three decimals at two widths in a row.
Click a row to draw its interval.
Derivative
R
Secant trail
A faint copy of the secant line is drawn for each wider interval in the table.