U1 A1- Polynomial Functions And Operations Flashcards
Do you factor the simplified expression once you add/subtract polynomial functions
No
In f(x)-g(x) what do you have to remember
Put ALL of g(x) into brackets and apply the negative to the whole expression
What is the order of operations for -x^2
1) square first
2) then apply the negative sign
What does it mean when a function is defined
It has an equation
When functions aren’t defined how do you find the sum or difference
Add/subtract the y values (outputs) at a given x value (input)
Given:
F(-3)=5
g(-3)=8
What is f(-3) + g(-3)
13
The domain of the combined sum or difference function may be ______ than the _____ domain
The range of the combined function can be determined from the _____
Different
Individual
Graph
F(x) domain: (-infinite,3)
g(x) domain: (-5,infinite)
What is the domain of (f+g)(x)
(-5,3)
The domain and range of a graph is always ____ unless there are restrictions
Infinite
x is an element of real numbers
How do you know if domain and range aren’t infinite when just given equation
If there are restrictions in the equation
What are 2 examples of restrictions on an equation
- x under a square root sign
- dividing something by x
What is the constant of a quadratic function (in terms of graphing)
y-intercept
The domain of the product or quotient function may be ______ than the _____
Different
Individual
The range of a combined function (multiplication or division) can be determined from the ____
Graph
How do you draw a new graph when you combine two functions
1) make a table and state the y-value of f(x) and g(x) at x values that you pick
2) combine the two y-values however you’re supposed to (add/sub/mul/div) And those are your new y-values
When you are determined a simplified expression for multiplication or division of polynomials should you factor after
No
How to determine the degree of a function multiplication statement without foiling it out
Count the x’s
(Linear function )(linear function)= _________
and why
Quadratic
(x)(x)=x^2
What is always the domain of a quadratic unless there are restrictions
Infinite
x is an element of real numbers
When is the only time you can add/subtract radicals
When the radicand are like terms
What is a radicand
Stuff under root sign
Before you state NPV’s what do you always have to do
Factor the expression
A discontinuity is a _____ in the graph
Graph
Vertical asymptote- a line that the graph _____ but never touches
Approaches
A vertical asymptote occurs when a ration expression cannot be ______ further
Simplified
Identify the vertical asymptote in
y=(x-4)/(x-1)
Restriction: x can’t equal (1)
Since ORIGINAL EXPRESSION can’t simplify further,
x= (-1) is vertical asymptote
Point of discontinuity- a single ___ that doesn’t exist on the graph
Point
A point of discontinuity occurs when a rational expression ___ be simplified further
Can
Identify the point of discontinuity in the expression
y= [(x-1)(x+2)]/(x-1)
Restriction: x can’t equal (1)
Expression can be simplified further to (x+2) so x=1 is a point of discontinuity
Then sub the x value into the expression to get the y-value
The y-value of a point of discontinuity can be found by _______ the restricted x-value into the _____ expression
Substituting
Simplified
What is quotient to anything divided by 0
And what does this mean in terms of functions
Undefined
Know that this is a point of discontinuity
(look at the x-value and plug it in to find the y value of the hole)
(Quadratic function)/(linear function)=_______
and why
Linear function
X^2)/(x)=(x
How do you solve 3(fg)(2)
1) evaluate the product of (f)(g) when x is 2
2) multiply the whole thing by 3
When adding/subtracting polynomials fractions you need ______
LCD’s
Can you cancel binomials in division if they’re not the EXACT same expression
No
When multiplying/dividing functions a NPV will result in a ______ or _____
Vertical asymptote
Point of discontinuity
To draw the graph of functions being multiplied/divided you multiply the two ____ values at the same ____ value
Y
X
Composite functions- ____ within functions
Functions
How do you write (f dot g)(x) as a composite function
f[g(x)]
To find the equation for composite functions, ______ the inside function for x in the ____ function
Substitute
Outside
To evaluate composite functions, evaluate the ____ function at the given ___ value then take this output and evaluate the _____ function at the ____ x value
Inside
X
New
How to find domain of composite functions
Combine the domains of each function
Identify any restrictions and state domain (as we always do)
Composite functions- if the inner function isn’t defined, neither is the _____ function
Composite