Day 3 Lesson 15 Geometric Sequences and Series

Determine whether each sequence is geometric or not.

Groups:

(a) Geometric Sequence

,

(b) Not a Geometric Sequence

• 64, 96, 144, 216, ...

• 7, 14, 21, 28, ...

• 5, -5, 5, -5, ...

Find the common ratio and the next term of each geometric sequence.

a) 2/3, 4, 24, 144, ...

r =​ (a)   ; a_{5 =}​​ (b)  

b) 9, -3, 1, -1/3, ...

r =​ (c)   ​ ; a_{5 =}​​ (d)  

• 6
• 864
• 1/9
• -1/3
• 4
• -3
• 1
• 576

Find the missing terms of the geometric sequence:

-3, ​ (a)   ​, (b)   , 648, ...

• 18
• -108
• 72
• -216
• 431
• 214

• 
• 
• 
• 

Mathematical Equivalence

ON

What is the partial sum of the geometric series, 2 + 10 + 50 + ... + 6250?

Mathematical Equivalence

ON