Chapter 5

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Algebra 2 Final Review
Study Outline
• Chapter 5:
• Chapter 6:
• Chapter 7&9:
• Chapter 11:
• Chapter 13:
• Chapter 8:
Quadratic Functions
Polynomial Functions
Functions and Inverses
Exponential and
Logarithmic Functions
Statistics
Trigonometry
Rational Functions
Chapter 5: Quadratic Functions
Standard Form: 𝑓 π‘₯ = π‘Žπ‘₯ 2 + 𝑏π‘₯ + 𝑐
Vertex Form: 𝑓 π‘₯ = π‘Ž(π‘₯ − β„Ž)2 +π‘˜ with Vertex (h,k)
Axis of Symmetry: π‘₯ =
𝑏
−
2π‘Ž
Ex. Find the axis of symmetry for the parabola given
by 𝑓 π‘₯ = −π‘₯ 2 + 8π‘₯ − 9.
Vertex
The maximum or minimum point of a parabola.
𝑏
−
2π‘Ž
From standard form, use π‘₯ =
to find the π‘₯coordinate and then plug that into the function to
find the 𝑦 −coordinate.
You can also find the vertex by graphing the
function and using the minimum/maximum feature
on your calculator.
Ex. Find the vertex of 𝑓 π‘₯ = π‘₯ 2 − 4π‘₯ + 7.
Transformations
𝑓 π‘₯ =π‘Ž π‘₯−β„Ž
2
+π‘˜
Ex. Write a function for a parabola that is
reflected across the π‘₯ axis, vertically stretched
by a factor of 5, and translated 3 units to the
right and 9 units down.
Ex. Describe the transformations given by the
1
function 𝑓 π‘₯ = π‘₯ + 3 2 + 9 .
4
Solving Quadratic Equations
•
•
•
•
•
Graphing
Factoring
Square-Rooting
Completing the Square
Quadratic Formula
Quadratic Formula
Used to find roots of quadratic equations.
π‘₯=
−𝑏± 𝑏2 −4π‘Žπ‘
2π‘Ž
π·π‘–π‘ π‘π‘Ÿπ‘–π‘šπ‘–π‘›π‘Žπ‘›π‘‘ = 𝑏 2 − 4π‘Žπ‘
Used to determine the number and types of
roots of a given quadratic equation.
Note: roots = zeros = solutions = x-intercepts
Quadratic Formula
Find the roots of π‘₯ 2 − 2π‘₯ + 5 = 0
Discriminant
π·π‘–π‘ π‘π‘Ÿπ‘–π‘šπ‘–π‘›π‘Žπ‘›π‘‘ = 𝑏 2 − 4π‘Žπ‘
Ex. Find the discriminant of the function 𝑓 π‘₯ =
− 2π‘₯ 2 + 5π‘₯ − 9.
Based on the discriminant, determine the
number and types of roots of the function.
Completing the Square
Find the value of 𝑐 to complete the square,
creating a perfect square trinomial.
Ex. π‘₯ 2 − 8π‘₯ + 𝑐
Irrational Numbers
𝑖 = −1
𝑖 2 = −1
Ex. Simplify (3 + 2𝑖)(2 − 4𝑖)
Chapter 6: Polynomial Functions
Characteristics of a polynomial:
 Degree: Highest power
 Leading Coefficient: Coefficient of term with
highest power
 Number of Terms
Ex. 𝑓 π‘₯ = −8π‘₯ 5 + 2π‘₯ 2 − 7π‘₯ 9
End Behavior
Step 1: Leading coefficient (right side)
 Positive: Right side rises
 Negative: Right side falls
Step 2: Degree (both ends)
 Even: both ends go in the SAME direction
 Odd: the ends go in OPPOSITE directions
End Behavior
Ex. Describe the end behavior of the function:
𝑓 π‘₯ = −3π‘₯ 7 + 5π‘₯ 3 − 2π‘₯ = 10
Add/Subtract/Multiply
Adding  combine LIKE terms
Subtracting  remember to distribute the –
Ex. 3π‘₯ 5 − 9π‘₯ 2 − 10 − (2π‘₯ 5 − 3π‘₯ 4 + 5π‘₯ 2 )
Ex. (π‘₯ − 3)(π‘₯ 2 + 2π‘₯ − 1)
Solving Polynomial Equations
To solve ALGEBRAICALLY:
• Factor completely
• Set each factor = 0 and solve for x
Ex. 5π‘₯ 4 − 10π‘₯ 2 = 0
Note: Remember that the degree tells you how
many total solutions there are.
Solving Polynomial Equations
To solve GRAPHICALLY, find the x-intercepts:
Ex. 3π‘₯ 4 + 24π‘₯ 3 + 48π‘₯ 2 = 0
Multiplicity of Roots
• On a graph, we can tell the multiplicity of a
root because an even multiplicity will
“bounce” off the π‘₯-axis while an odd
multiplicity will “bend” through the π‘₯-axis.
• Find the roots and state the multiplicity of
each for 𝑓 π‘₯ = π‘₯ 4 π‘₯ − 1 3
Chapters 7 & 9:
Functions & Inverses
Exponential Functions
Find the inverse:
Ex. 𝑓 π‘₯ =
π‘₯+6
2
Composition of Functions
Use the answer from one function as the input
in the other function.
Ex. Given 𝑓 π‘₯ = −3π‘₯ − 5 and 𝑔 π‘₯ = π‘₯ 2 , find:
𝑓 𝑔 2
𝑔(𝑓 2 )
Exponential Functions:
Growth and Decay
𝑓 π‘₯ = π‘Ž βˆ™ 𝑏π‘₯
 Growth when 𝑏 > 1
 Decay when 0 < 𝑏 < 1
 π‘Ž is 𝑦-intercept
Ex. Determine the y-int, base, growth or decay
𝑓 π‘₯ = 3 1.03 π‘₯
𝑔 π‘₯ = 0.95π‘₯
Exponential Growth and Decay
𝐴=𝑃 1±π‘Ÿ
𝑑
Ex. An investment of $4,250 is said to gain value
at 4% annually. How long will it take the
investment to be worth $6000?
Solving Exponential Equations
Solve:
Ex. 165π‘₯ = 64π‘₯+7
Ex. 25π‘₯ =
1 2−π‘₯
125
Logarithmic Expressions
Definition of log: log 𝑏 π‘Ž = 𝑝 ↔ 𝑏 𝑝 = π‘Ž
Rewrite each expression in the “other” form:
3
−2
=
1
9
log 4 64 = 3
Logarithmic Properties
• Product Rule: log 𝑏 π‘₯ + log 𝑏 𝑦 = log 𝑏 π‘₯ βˆ™ 𝑦
• Quotient Rule: log 𝑏 π‘₯ − log 𝑏 𝑦 =
• Power Rule: log 𝑏 π‘₯ 𝑝 = 𝑝 βˆ™ log 𝑏 π‘₯
π‘₯
log 𝑏
𝑦
Logarithmic Properties
• Express the following as a single logarithm.
• log 4 32 + log 4 2
Solving Exponential or Logarithmic
Equations
• When it is not possible to get “like bases” take
the log of both sides, rewrite the equation and
solve.
• Ex. 4π‘₯ = 18
Solving Exponential or Logarithmic
Equations
• A logarithmic equation:
– Condense
– Rewrite as an exponential equation
– Solve
• Ex. log 2 4 + log 2 π‘₯ = 6
Logarithmic Functions
• Logarithmic functions: 𝑓 π‘₯ = log 𝑏 π‘₯
– Domain: π‘₯ > 0
– Range: All Real Numbers
– π‘₯ −intercept: π‘₯ = 1
– 𝑦 −intercept: None
Chapter 11: Statistics
• Linear Regression and Exponential Regression
– Enter the data into L1 and L2
– Stat -> Calc -> 4: LinReg(ax+b)
• 𝑦 = π‘Žπ‘₯ + 𝑏
– Stat -> Calc -> 0: ExpReg
• 𝑦 = π‘Ž βˆ™ 𝑏π‘₯
Exponential Model
• Given the following data, find the equation of
the exponential model.
Years after 1970
Population (in millions)
0
203.3
10
226.5
20
248.7
30
281.4
Correlation
• The correlation, π‘Ÿ, measures the strength and
direction of a linear relationship.
• π‘Ÿ close to 1 OR -1 is strong
• π‘Ÿ close to 0 is weak.
Mean
• Find the mean from the frequency table:
Score
Frequency
90
3
92
8
95
11
99
2
Standard Deviation
• Standard deviation measures the “spread” or
“variability” of the data.
• A small standard deviation indicates data that
are all very similar.
• A large standard deviation indicates data that
are very different.
Normal Distribution
• Remember the 68 – 95 – 99.7% rule
Normal Distribution
• Test scores were normally distributed with a
mean of 100 and standard deviation of 10.
What percent of students scored between an
80 and 120?
Types of Studies
• Survey: a questionnaire given to a sample of
individuals.
• Observational Study: gather data on a topic
without manipulating any variable
• Experiment: purposefully manipulate one
variable to examine its effect on another
variable
Types of Studies
• Categorize each type of study:
• A college sends a feedback postcard to students
who recently attended an open house.
• A researcher compares the SAT scores of students
taking Latin with students not taking Latin.
• The number of heart attacks is compared when
one group of individuals are assigned to take an
aspirin a day while another group does not not.
Chapter 13: Trigonometry
• SOH-CAH-TOA
• Given the triangle, find the value of the three
trig functions.
Angle of Elevation or Depression
• A road rises 10 feet over a horizontal distance
of 80 ft. Find the angle of elevation of the
road.
Angles of Rotation
•
•
•
•
Positive = Counterclockwise
Negative = Clockwise
Draw each angle in standard position:
πœƒ = 210°
πœƒ = −100°
Coterminal Angles
• Coterminal angles are in the same position.
• Add or subtract multiples of 360°.
• Find two angles coterminal with πœƒ = 40°.
Reference Angles
• Think reference to the π‘₯-axis.
• Find the reference angle for each angle.
• πœƒ = 200°
πœƒ = 300°
Points on the Terminal Side of πœƒ
• Point P(5, -12) is on the terminal side of πœƒ
when drawn in standard position. Find the
values of sin πœƒ, cos πœƒ, and tan πœƒ.
Radians and Degrees
• 180° = πœ‹ π‘Ÿπ‘Žπ‘‘π‘–π‘Žπ‘›π‘ 
• Convert to the “other” measurement.
• 210°
5πœ‹
6
Exact Value or Unit Circle
sin πœƒ
cos πœƒ
tan πœƒ
πŸ‘πŸŽ°
πŸ’πŸ“°
πŸ”πŸŽ°
1
2
3
2
3
3
2
2
2
2
3
2
1
2
1
3
Exact Value of Sin, Cos, Tan
• Find the reference angle. (Convert to degrees
if necessary.)
• Use the table of exact values.
• Decide if the function should be positive or
negative by using A-S-T-C.
Exact Value of Sin, Cos, Tan
• Find the exact value of:
sin 210°
7πœ‹
cos
4
Exact Value of Sin, Cos, Tan
• Find the value of the angle that is the solution
to: tan
−1
3
3
Pythagorean Identity
• Remember that sin2 πœƒ + cos2 πœƒ = 1
Graphs of Sine/Cosine
• Amplitude = |a|
• Graph 𝑦 = 2 sin π‘₯
Period =
2πœ‹
𝑏
Graphs of Sine/Cosine
• Amplitude = |a|
• Graph 𝑦 = cos πœ‹π‘₯
Period =
2πœ‹
𝑏
Maximum and Minimum Value for
Sine and Cosine
• Given 𝑦 = π‘Ž sin 𝑏π‘₯ + π‘˜, the max or min values
can be found by: π‘˜ ± π‘Ž.
• Find the max/min values of each function:
𝑦 = 2 sin 3π‘₯
𝑦 = 3 cos πœ‹π‘₯ + 5
Chapter 8: Rational Expressions and
Equations
• Simplify by factoring, then canceling factors in
common.
9π‘₯ 2 𝑦
10π‘₯𝑦 3
βˆ™
5π‘₯
3𝑦
π‘₯ 2 −4
3π‘₯−9
π‘₯+2
÷
π‘₯−3
Restricted Values of π‘₯
• Remember that 0 cannot be in the
denominator!
• Simplify and state the restricted values of π‘₯
4π‘₯ + 4
π‘₯ 2 − 8π‘₯ − 9
Solving Rational Equations
• Determine the LCD. Multiply EACH term by
the LCD. Simplify and solve. Check for
extraneous solutions.
• π‘₯
12
+
π‘₯
=7
Solving Rational Equations
•
π‘₯+4
π‘₯
+
π‘₯−6
2
=
10
π‘₯−6
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