Memorization, a contemptuous, futile, and insignificant method of learning math is, I think, not the solution to my problem. Well for the arithmetical progression, I have the formula:(adsbygoogle = window.adsbygoogle || []).push({});

Let: l= last term

a= first term

d= common difference

l= a+[d(n-1)]

And for the geometrical progression;

Let: l= last term

a= first term

r= common ratio

l= a(r^n-1)

and also,

for the getting the sum;

Let: l= last term

r= common ratio

a= first term

S= lr-a/ r-1

Now given these formulas, I have no idea how it is derived. I tried to formulate it on my own but I don't know how these equation was created. Please, give me tips to discern how a formula is made.

**Physics Forums - The Fusion of Science and Community**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Formulas for Arithmetical and Geometrical Progression

Loading...

Similar Threads - Formulas Arithmetical Geometrical | Date |
---|---|

B Find the missing energy value given a set of data (Hypothetical question) | Mar 3, 2018 |

B Can you please tell me the origin of this formula? | Feb 24, 2018 |

I Proof without words for Heron's formula | Jan 19, 2018 |

Arithmetic Progression formula proof | Apr 22, 2012 |

Check my arithmetic for this formula. | Mar 9, 2009 |

**Physics Forums - The Fusion of Science and Community**