Sequences Series and Sigma Notation

What is the rule for the n^th term given  60, 55, 50, 45, ...

• a_n= 60n - 5

• a_n= -5n + 55

• a_n= -5n + 65

• a_n= 5n + 55

• 13

• 11

• 10

Write 1 + 2 + 3 + ... + 10 using sigma notation

Write 1 + 4 + 9 + ... + 49

using sigma notation

• 3 + (-6) + 18

• 3 + (-6) +12

• 3 + (-6) + 12 + (-24

• -6 + 12 + (-24) + 48

Write the formula for the n^th term:  3.5, 7, 14, 28, 56

• a_n = 3.5(0.5)^n-1

• a_n = 2n + 1.5

• a_n = 3.5n

• a_n = 3.5(2)^n-1