# Thread: The formulas for Algebraic Sequences and Geometric Sequences

1. ## The formulas for Algebraic Sequences and Geometric Sequences

This is for geometry.

Is the formula for an Algebraic Sequence: a+d(n-1).

Is the formula for an Geometric Sequence: a * (TIMES) r^n-1.?

If so could so one give me an example of each? Thanks

2. Originally Posted by zachcumer
This is for geometry.

Mr F edits in red:

Is the formula for the nth term of an Arithmetic Sequence: a+d(n-1)

Is the formula for the nth term of a Geometric Sequence: a * (TIMES) r^n-1.?

If so could so one give me an example of each? Thanks
Yes.
Yes.

3. is the formula for the sum of all angles (n-2) times 180?

4. That's an interesting question... How many angles are there? I would guess a near infinite number, or at least on a scale that is far past countable. I can see nearly seven thousand from where I'm sitting, and the universe is pretty big. I'm going to make the assumption that the mean of all angles is around 45 degrees, though I can't justify that at all. Altogether then, the sum of all angles must be 45 times infinity, which I believe is... infinity.

Unless you made them all coterminal, and just let it loop in circles from zero to 360. Then your answer is fourteen.