**Introduction**

This program estimates the value of a derivative at a point
using the difference quotient

If you have not used one of the programs posted on this website before,
you should read through
the information in the Intro to Programming
section first.

**The Program **

:Disp "A" | {Disp is in PRGM under I/O} |

:Input X | {Input is in PRGM under I/O} |

:Disp "H" | |

:Input H | |

:Y1B | {Y1 is in Y-VARS under FUNCTION} {The arrow is STO} |

:X+HX | |

:Y1C | |

:(C-B)/HD | |

:Disp D |

**Running the Program**

You will need to enter a function *f*(*x*) into Y1 before running
the program. To test the program try the following:

*f*(*x*) = x^{3}, A=2, H=0.01.

The answer should be 12.0601