FINDING THE RANGE OF ON-SCREEN GRAPHS
Sometimes after entering an equation or scrolling or zooming around the grid, you may discover that you have lost one or more of the graphs you were interested in. To quickly "find" them again, you can often use the Find All Graphs item in the View menu to adjust the y-axis range to encompass the range of all the plots that are technically on-screen even though their plot may not show up within the current range.
If you find yourself using this command frequently, you may want to turn on the AutoRange feature, which essentially performs the Find All Graphs command for you whenever more than 20% of the plot for a new equation you have entered falls outside of the current grid range.
Note: Find All Graphs only works for Cartesian functions of x. Since the mechanism used to quickly "find" the extrema of the functions on-screen depends on performing Newton's method, which is only supported for this subset of graphs, functions of y, polar and parametric plots, ODEs, and implicit functions of x and y are not taken into account when computing the bounding range.