Calculates a 3^{rd} degree polynomial.

This is provided as a general formula that can be used by changing the constants.

Formula: c0 + c1*x0 + c2*x0^2 + c3*x0^3

For the polynomial Fx = -2 -1.5*x + 0.75*x^2 + 0.25*x^3

find f(3) and the roots.

Value | Key | Display | Description |
---|---|---|---|

-2 | C0 | -2.0000 | Stores the C0 value. |

-1.5 | C1 | -1.5000 | Stores the C1 value. |

.75 | C2 | 0.7500 | Stores the C2 value. |

.25 | C3 | 0.2500 | Stores the C3 value. |

3 | X | 3.0000 | Stores the X value. |

f(x) | 7.0000 | Calculates Fx(3). |

Find the root nearest to x = 3.

These keystrokes assume the values from example 1.

Value | Key | Display | Description |
---|---|---|---|

0 | f(x) | 0.0000 | Stores the Fx value. |

X | 2.0000 | Calculates a root. |

Find the root nearest to x = -3.

These keystrokes assume the values from examples 1 and 2.

Value | Key | Display | Description |
---|---|---|---|

-3 | X | -3.0000 | Stores a new initial guess. |

X | -4.0000 | Calculates a root. |

Find the root nearest to x = 0.

These keystrokes assume the values from examples 1 and 2.

Value | Key | Display | Description |
---|---|---|---|

0 | X | 0.0000 | Stores a new initial guess. |

X | -1.0000 | Calculates a root. |

Create a graph of for x = -5 to 3

Value | Key | Display | Description |
---|---|---|---|

-5 | = or ENTER | -5.0000 | Enters first value of the range. |

3 | shift f(x) | graph | Enters the second value of the range, selects the independent variable for the graph. |

This will produce the following graph

Please see the Formula Graph page on how to use the graph features.

Please note that the independent variable range can be entered in any order, minimum-maximum or maximum-minimum.

Reference: