# Document 15957136

```Math 1314 – Test #4 Review Topics – Ch. 6 &amp; 8
15 problems --- All are short answer/partial credit
(5 problems from Ch. 6  6 or 8 pts each)
(9 problems from Ch. 8  6 or 7 pts each)
(1 matching problem with formulas  1 point each)
Topics (from Chapter 6):
Writing an augmented matrix
Perform Gaussian Elimination (ROWOPS)
Solve a system using back-substitution
How to write non-unique solutions (no solution vs. infinite solutions)
Topics (from Chapter 8):
Write out the first few terms of a sequence
Determine a particular term in an arithmetic sequence
Write a formula for the nth term of an arithmetic sequence
Find the sum of several terms of an arithmetic sequence
Determine a particular term in a geometric sequence
Write a formula for the nth term of a geometric sequence
Find the sum of several terms of a geometric sequence
Calculate a sum (summation notation)
Calculate an infinite geometric sum
Formulas to “Memorize”:
an  a1  (n  1)d
an  a1  r 
S 
n 1
(r ≠ 0)
a1
1  r  where |r| &lt; 1
Sn =
Sn =
n
 a1  an 
2
a1 1  r n 
1  r 
(r ≠ 0, 1)
```