pi (π)=3.1415926535 ...

Shape | Formula | |
---|---|---|

◯ | Circle | 2 × pi × radius |

◻ | Square | 4 × side |

⌷ | Rectangle | 2 × (length + width) |

▱ | Parallelogram | 2 × (side1 + side2) |

△ | Triangle | side1 + side2 + side3 |

⬠ | Regular n-polygon | n × side |

⏢ | Trapezoid | height × (base1 + base2) / 2 |

⏢ | Trapezoid | base1 + base2 + height × [csc(theta1) + csc(theta2)] |

⬭ | Ellipse | 4 × radius1 × E(k,pi/2) E(k,pi/2) is the complete elliptic integral of the second kind k = (1/radius1) × sqrt(radius1 ^{2} - radius2^{2}) |

Source: Spiegel, Murray R. Mathematical Handbook of Formulas and Tables.

Schaum's Outline series in Mathematics. McGraw-Hill Book Co., 1968.