Algebra 2 1.1-1.4
range
The possible values of the output, or dependent variable, of a relation or function.
Function
1. A relationship from one set (called the domain) to another set (called the range) that assigns to each element of the domain exactly one element of the range. 2. The action or actions that an item is designed to perform. MEANS Y=
Sequence
A function whose domain is the natural numbers. Eg 3,5,7,9,11
Step graph
A graph that looks like steps. The values are the same for an interval and then "step" to the next interval.
arithmetic sequence
A sequence in which the difference between any two consecutive terms is the same.
explicit definition
Allows you to find any term in the sequence without knowing the previous term. An = a1 + d(n-1)
Transformation of a function
An alteration of a relation (either reflect across axis, stretch/compress, move vertical or horizontal')
Translation
a transformation that shifts or slides every point of a figure or graph the same distance in the same direction without changing the size, shape or rotation
Horizontal compression and stretch
G(x) = f(ax) (graph move closer (stretch) or father away (compression) from y-axis "a" units). Eg. F(1/2x) = 2/1 • x = y
common difference
In an arithmetic sequence, the nonzero constant difference of any term and the previous term. D = 2
{x| x is a real number }
Indicate set {}, x is variable, | means such that
Horizontal translation
Left: g(x) = f(x+h) (subtract h units to x value). Right: g(x) = f(x-h) (add h units to x value) ANY MANIPULATION TO X WILL BE INVERSE OF ORIGINAL SIGH
interval notation
Represent a set of real numbers by the pair of values where the left is the minimum and right is the maximum.
Finite Arithmetic Series
Sn=n/2(a1+an). The Sum of n terms with first term A1 and last term An. the sum of terms in an arithmetic sequence. FOR SUM OF n NUMBERS IN A SEQUENCE, use RECURSIVE FORMULA or add terms
sigma notation
Sum of n terms of a sequence written using... Index i counts through the terms in partial series. Values from 1 up to n, last term in partial series. The value of the ith term is ai. Use explicit formula for the sequence in place of ai
Finite Series
Sum of the terms in a finite sequence. a series with a finite number of terms.
Domain
The possible values for the input of a relation or function
Maximum of a function
The y-value of the highest point on the graph of a function. Point where function change from increasing to decreasing
Minimum of a function
The y-value of the lowest point on the graph of a function. Increasing to decreasing
recursive definition
a sequence defined by giving the first term (or the first few terms) along with a procedure for finding the subsequent terms. F(n) = f(1), n= 1 and f(n-1) + d, n>1
Vertical translation
Up: g(x) = f(x) + k. Down g(x) = f(x) - k. Move the y value k units
set-builder notation
Verbal description or inequality to describe the numbers of a function's domain or range
Write rule for an absolute value function (1.3)
Write function in form of f(x) = a|x-h| + k to find vertex of function. Then determine slope and equation of each piece on opposite sides of x value. Then write piecewise defined function
X and y intercept
X intercept- line crosses x axis and so y value =0. Y intercept- line cross y axis and x =0
Reflection over axis
Y axis: g(x) = f(-x) (reverse x coordinate and keep y). X axis: g(x) = -f(x) (reverse y coordinate, keep x the same)
What do [] and () mean
[] include the x value when graphing or value and (greater/ less than or equal too) closed. () not include the value when graphing or value. <> closed
piecewise-defined function
a function that has different rules for different parts of its domain. A function that is defined using two or more expressions for different intervals of the domain.
Average rate of change
f(b)-f(a)/b-a. Slope of secant line between two points, use to estimate instantanous rate of change at a point. Slope of a line; y2-y1/x2-x1
vertical stretch/compression
g(x)=af(x). (Graph move closer (compression ) or farther away (stretch) from the x axis)