sequence or series?
2, 3, 5, 7, 11, 13
*bonus: name the pattern*
sequence
*bonus: prime numbers*
find the common difference or the common ratio:
78, 75, 72, 69, 66, ...
`d=-3`
what is the explicit formula for arithmetic sequence?
`an=a1+(n-1)d`
find the sum:
`1-1/2+1/4-1/8+...`
`2/3`
finite or infinite?
2, 4, 6, 8, 10, 12, 14, 16, 18, 20
finite
find the common difference or the common ratio:
`3/32,3/16,3/8,3/4,3/2,...`
r=2
what is the explicit formula for a geometric sequence?
`an=a1*r^(n-1)`
`sum_(n=1)^8(3n+1)`
116
arithmetic, geometric, or neither?
-4, 2, 8, 14
arithmetic
find the common difference or the common ratio:
1620, 540, 180, 60, ...
`r=1/3`
what is the formula for the sum of an infinite geometric series?
`S=(a1)/(1-r)`
`sum_(n=2)^6(-2)^(n-1)`
-22
Find the sum:
`6+5+25/6+...`
36