# Equation Grapher

Enter an Equation using the variables x and/or y and an =, press Go:

(Note: there is also the Flash Version.)

## Description

It can plot an equation where x and y are **related somehow** (not just y=...), like these:

### Examples:

**x^2+y^2=9**(an equation of a circle with a radius of 3)**sin(x)+cos(y)=0.5****2x-3y=1****cos(x^2)=y****(x-3)(x+3)=y^2****y=x^2**

If you don't include an equals sign, it will assume you mean "**=0**"

It has not been well tested, so **have fun** with it, but **don't trust it**.

If it gives you problems, let me know.

Note: it may take a few seconds to finish, because it has to do lots of calculations.

If you just want to graph a function in "y=..." style you may prefer Function Grapher and Calculator

## Zooming

Use the zoom slider (to the left zooms in, to the right zooms out).

To reset the zoom to the original bounds click on the **Reset** button.

## Dragging

Click-and-drag to move the graph around. If you just click-and-release (without dragging), then the spot you clicked on will be the new center

Note: the plots use **computer calculations**. Round-off can cause errors or values can be missed completely.

## All Functions

### Operators

+ | Addition operator | |
---|---|---|

- | Subtraction operator | |

* | Multiplication operator | |

/ | Division operator | |

^ | Exponent (Power) operator |

### Functions

sqrt |
Square Root of a value or expression. | |
---|---|---|

sin |
sine of a value or expression | |

cos |
cosine of a value or expression | |

tan |
tangent of a value or expression | |

asin |
inverse sine (arcsine) of a value or expression | |

acos |
inverse cosine (arccos) of a value or expression | |

atan |
inverse tangent (arctangent) of a value or expression | |

sinh |
Hyperbolic sine (sinh) of a value or expression | |

cosh |
Hyperbolic cosine (cosh) of a value or expression | |

tanh |
Hyperbolic tangent (tanh) of a value or expression | |

exp |
e (the Euler Constant) raised to the power of a value or expression | |

ln |
The natural logarithm of a value or expression | |

log |
The base-10 logarithm of a value or expression | |

floor | Returns the largest (closest to positive infinity) value that is not greater than the argument and is equal to a mathematical integer. | |

ceil | Returns the smallest (closest to negative infinity) value that is not less than the argument and is equal to a mathematical integer. | |

round | Round to the nearest integer. Examples: round(-2.5) = -2, round(-0.1) = 0, round(0.1) = 0, round(2.5) = 3 | |

abs | Absolute value (distance from zero) of a value or expression | |

sign | Sign (+1 or -1) of a value or expression | |

### Constants

pi | The constant π (3.141592654...) | |
---|---|---|

e | Euler's number (2.71828...), the base for the natural logarithm |