Unit: Functions and Mathematical Models Lesson: Introduction to Functions
Functions: A function is a relation that pairs each element from the domain with exactly one element of the range
Algebraic: f(x)=
Graphic:
Numeric:
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Lessons 1.1-1.3 Introduction to Functions
Is it a function? Yes or No. If no, why not?
In function notation, the symbol f(x) is read f of x, x is called the independent variable. A value in the range of f is represented by the dependent variable y. Equation form:
Function Notation
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What does that 6 indicate?
Find
a)
b)
Domain: The domain of a function is the complete set of possible values of the independent variable The domain defines the horizontal boundary points of the function. Interval Notation:
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Domain:
Interval Notation:
The range defines the vertical boundary points of the function.
Range:
Interval Notation:
Finding Domains Algebraically
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Summary of Restricted Domains
fraction: radical: fraction with a radical in the denominator:
You Try -
1.
4.
2. 5. 3.
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Continuity: A graph is a continuous function if it has no breaks, holes or gaps. If it has one or more of those then it is discontinuous.
Types of Discontinuity A function has infinite discontinuity at x=c if the function value increases or decreases indefinitely as x approaches c from the left and right.
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Types of Discontinuity A function has jump discontinuity at x=c if the limit of the function as x approaches c from the left and right exist but have two distinct value.
Types of Discontinuity A function has a point discontinuity if the function is continuous everywhere except for the hole at x=c
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State if the function is continuous or discontinuous. If it is discontinuous state c.
State if the function is continuous or discontinuous. If it is discontinuous state c.
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End Behavior: the end behavior of a function describes how a function behaves at either ends of the graph. Left End Behavior what is happening at the extreme left of the graph.
Calculus Notation: Pre Calculus Notation:
As
Right End Behavior what is happening at the extreme right of the graph.
Calculus Notation: Pre Calculus Notation:
As
End Behavior
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End Behavior
End Behavior
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Even Function: A function f is even if the graph of f is symmetric with respect to the yaxis. Algebraically, f is even if and only if f(-x) = f(x) for all x in the domain of f.
Odd Function: A function f is odd if the graph of f is symmetric with respect to the origin. Algebraically, f is odd if and only if f(-x) = -f(x) for all x in the domain of f.
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Is the function odd even or neither?
State the Type of Symmetry
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Unit: Functions and Mathematical Models Lesson: Introduction to Functions Day 2
Increasing and Decreasing
Increasing: A function is in increasing on an interval if and only if for any two points in the interval, a positive change in x results in a positive change in f(x).
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Decreasing: A function is in decreasing on an interval if and only if for any two points in the interval, a positive change in x results in a negative change in f(x).
The challenge comes in when the function is both increasing and decreasing.
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State the increasing and decreasing intervals
State the increasing and decreasing intervals
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State the increasing and decreasing intervals
(-2,2) (0.5,-1.25)
(-1,7)
The point we labeled on the graph are the extrema. They are the points at which the function changes its increasing or decreasing behavior. The points themselves are called critical points. Any maximum or minimums MUST occur at a critical point.
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Relative and Absolute Maximum: A relative maximum of a function f is the greatest value f(x) can have on some interval of the domain. Quartic - negative leading coefficient
If a relative maximum is the greatest value the function can attain over its entire domain, then it is the absolute maximum.
Relative and Absolute Minimum: A relative minimum of a function f is the least value f(x) can have on some interval of the domain. If a relative minimum is the least value the function can attain over its entire domain, then it is the absolute minimum. Quartic - positive leading coefficient
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State all of the extrema
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State all of the extrema and the increasing or decreasing intervals.
What is the slope?
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To find the slope on an interval of a curve you need to use one of two formulas:
Average Rate of Change =
or
Find the Average Rate of Change
on the interval
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Find the Average Rate of Change
on the interval
Given
find the average rate of change formula
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Given
find the average rate of change formula
Find the average rate of change for the function
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Evaluate that rate of change on the interval [2, 2.01] and [-3, -3.01]
Unit: Functions and Mathematical Models Lesson: Introduction to Functions Day 3
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For all of our problems today we will find the equation for the average rate of change and then evaluate it on a given interval.