Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.
Upcoming SlideShare
×

# Algebraic Sequences

18,587 views

Published on

This is a lesson/slideshow presentation I made for my 8th grade PreAlgebra students.

Published in: Education, Technology
• Full Name
Comment goes here.

Are you sure you want to Yes No
Your message goes here
• Thanks a lot. It helped my son to finish his home work.

Are you sure you want to  Yes  No
Your message goes here

### Algebraic Sequences

1. 1. Algebraic Sequences Obj. Generate an algebraic expression given part of a sequence.
2. 2. Algebraic Sequence <ul><li>A sequence which has a constant difference between terms. </li></ul><ul><li>Examples: </li></ul><ul><li>1, 5, 9, 13, 17 </li></ul><ul><li>-7, -1, 5, 11, 17 </li></ul><ul><li>21, 20, 19, 18, 17 </li></ul>
3. 3. EXAMPLE 1 Write an expression for the n th term in the sequence 3, 4, 5, 6, 7, …? Step 1 :  Construct a process chart showing the position and the corresponding term. 3 4 5 6 7 +1 +1 +1 +1 Position “ 0” 1 2 3 4 5 n Term
4. 4. Determine the common difference (the change) of the terms. STEP 2 Common Difference: 1 This is the coefficient of n . 1 n
5. 5. Reverse the pattern to find the “zero” term. STEP 3 3 4 2 5 6 7 -1 Zero term: 2 Position “ 0” 1 2 3 4 5 n Term
6. 6. Common Difference: 1 FINISHING IT OFF Zero Term: 2 1 2 n + 2 n +
7. 7. EXAMPLE 1 Write an expression for the n th term in the sequence 12, 8, 4, 0, -4, …? Step 1 :  Construct a process chart showing the position and the corresponding term. 12 8 4 0 -4 -4 -4 -4 -4 Position “ 0” 1 2 3 4 5 n Term
8. 8. Determine the common difference (the change) of the terms. STEP 2 Common Difference: -4 This is the coefficient of n . -4 n
9. 9. Reverse the pattern to find the “zero” term. STEP 3 12 8 16 4 0 -4 +4 Zero term: 16 Position “ 0” 1 2 3 4 5 n Term
10. 10. Common Difference: -4 FINISHING IT OFF Zero Term: 16 -4 16 -4 n + 16 n +
11. 11. Practice <ul><li>4, 9, 14, 19, 24 </li></ul><ul><ul><li>5n + -1 or 5n - 1 </li></ul></ul><ul><li>-8, -5, -2, 1, 4 </li></ul><ul><ul><li>3n + -11 or 3n – 11 </li></ul></ul><ul><li>7, 1, -5, -11, -17 </li></ul><ul><ul><li>-6n + 13 </li></ul></ul><ul><li>-15, -11, -7, -3, 1 </li></ul><ul><ul><li>4n + -19 or 4n – 19 </li></ul></ul>