#### graph controls help

• select a point by mousing over it. the red dot's coordinates will be displayed for each function down below.
• pan the graph by clicking and dragging.
• zoom in and out with the mouse wheel.
• reset the zoom level by pressing the middle mouse button (typically by pressing down on the scroll wheel).
• pan back to the origin and reset the zoom level by double clicking the middle mouse button.
• update the graph with new functions by pressing enter or pressing the large 'graph' button.
• select a point by touching it. the red dot's coordinates will be displayed for each function down below.
• pan the graph by double tapping and dragging.
• zoom in and out with a pinch and zoom gesture.
• update the graph with new functions by pressing the large graph button.

### functions

#### function help

each grey box represents one function. functions can be added with the three buttons at the bottom of the list.

• f(x) or y'(x, y) or y''(x, y, y') - enter your expression here using the given arguments. entries are not case sensitive. the following functions are supported:
• standard mathematical operators - +, -, *, /, ^. note that omitting multiplication operators (e.g. 2x) is not supported.
• trigonometric functions - sin(), cos(), tan(), arcsin(), arccos(), arctan()
• logarithms - ln(), exp()
• absolute value - abs()
• square root - sqrt()
• floor - floor()
• Heaviside step function - H(), or mu()
• Dirac delta function - delta()
• Stirling's Formula - gamma()

the constants pi and e are also available.

• x and y - these boxes are for output only. they display the coordinates of your currently selected point. if the function is undefined for an x value, NaN (not a number) will be displayed.
• remove - remove this function.
• domain - the values where this function is defined. infinity and negative infinity can simply be typed as "infinity" and "-infinity".

differential equations have some additional input boxes:

• initial x, initial y, and initial y' - specify the initial conditions of the differential equation.

### options

#### options help

• color - check this box to give every curve a unique color.
• points per x - the number of sample points that the program will compute in the length of one unit in the x axis. higher values increase the accuracy of the approximation, but will require more processing power.
• reset - resets everything, just as if you'd reloaded the page. nothing will be saved.
• export as image - lets you save the current graph as a png image. does not function on mobile browsers.