torisss.

I don't know what to do this blog on so im just gonna do it on the same one i did last week.

This week we did chapter 13.
the chapter is about sequences, which are a listing of numbers.
Each sequence is either arithmetic (adding the same number every term) or geometric (multipling by the same number for every term).
For this we have two formulas:
arithmetic formula: t*n = t*1 + (n-1)d
geometric formula: t*n = t*1 X r^n-1
For these formulas d is the number being added or subtracted and r is the number being multiplied by.
Or you may have to find certain terms.
Fo this you get a formula like t*n = #n -# and you make n the term you're looking for.
Some Examples:
#1: Find the first 5 terms of t*n = 2n - 9
t*1 = 2(1) - 9 = 2 - 9 = - 7
t*2 = 2(2) - 9 = 4 - 9 = -5
t*3 = 2(3) - 9 = 6 - 9 = -3
t*4 = 2(4) - 9 = 8 - 9 = -1
t*5 = 2(5) - 9 = 10 - 9 = 1
#2: 2, 4, 6, 8, 10
t*n = t*1 + (n-1)d
t*n = 2 + (n-1)2
t*n = 2 + 2n -2
t*n = 2n