Tuesday, January 28, 2014

Arithmetic and Geometric Sequences - General Forms of a Sequence


Arithmetic and Geometric Sequence
Sequence - an ordered list of terms or elements






Arithmetic sequence formula: In an Arithmetic Sequence, the difference between one term and the next is a constant. AKA the Common Difference.
ARITHMETIC FORMULA:
a=a1 +(n-1)d:
n: term number
a(n): nth term
a: first term
r: common difference

Geometric Sequence Formula: In a Geometric Sequence, each term is found by multiplying the previous term by a constant. AKA Common Ratio.
GEOMETRIC FORMULA:
an=a1 + r (n - 1):
n: term number
a(n): nth term
a: first term
r: common ratio

Example:        2, 4, 8, 16, 32, 64...
This sequence has a factor of 2 between each number. Each term ( except the first term ) is found by multiplying the previous term by 2.


Finite sequence - Function with domain 1, 2, 3.
Infinite sequence - Function with domain 1, 2, 3, 4....
Series - Sum of a sequence
Explicit formula - Each domain is an answer not based on any values.
Recursive formula - Each domain is an answer based on a previous answer

Tuesday, January 14, 2014

Characteristics of a Graph

~~Characteristics of a Graph~~




Domain : Left and Right
Range : Up and Down
End Behavior :Describing the two ends of the graph. While X approaches negative infinity, Y approaches negative infinity. While X approaches positive infinity, Y approaches positive infinity and vice versa in another situation.          
                                          Left X -> (-∞)   y→-∞         y→-∞
                                                                   y→+∞   ( Describe 2 Ends)
                                         Right X -> (+∞)  y→-∞       y→-∞
                                                                   y→+∞
Absolute Max/Min: 1 Point highest/lowest on graph - A specific point on a graph
Local Max/Min: More than 1 point highest/lowest on graph
Interval of Increase: Section of a graph where the y-values increase (-∞, 0) 
Interval of Decrease: Section of a graph where the y-values decrease (0, +∞)
X Intercept: (a,0) crosses X axis
Y Intercept: (0,b) crosses Y axis
Symmetry: Even/Odd/Neither
Even: about the Y - Axis
Odd: rational symmetry about the origin
Neither: no symmetry
Asymptotes: Imaginary line that the graph gets closer and closer yet it never touches 
Function: Passes VLT ( Vertical Line Test) 
One to One: Passes VLT/ HLT ( Horizontal Line Test)