
Thinkwell - Trigonometry
Thinkwell turns trigonometry from frustrating to fearless. Smart, lively lessons help students see the logic, find their rhythm, and finally feel confident solving problems that once felt impossible.
$169
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Thinkwell's Trigonometry
Thinkwell's Trigonometry provides a comprehensive high school trigonometry course through video instruction, interactive practice, and built-in assessment tools. Taught by award-winning professor Edward Burger, the course helps teens develop a strong understanding of trigonometric concepts while building the mathematical foundation needed for precalculus, calculus, physics, and other STEM studies.
Video lessons guide teens through topics such as angles and radian measure, trigonometric functions, graphing sine and cosine functions, inverse trigonometric functions, trigonometric identities, the Law of Sines, the Law of Cosines, vectors, complex numbers, and polar coordinates. The course also reinforces key algebra concepts and explores exponential and logarithmic functions, conic sections, and mathematical modeling. Professor Burger's clear teaching style helps teens understand not only how mathematical procedures work, but why they work.
Interactive practice exercises provide immediate feedback, allowing teens to identify mistakes, strengthen understanding, and build mastery as they progress through the course. Automatically graded exercises, quizzes, chapter tests, practice tests, a midterm exam, and a final exam provide regular assessment throughout the year.
The course includes progress-tracking tools, automatic grading, and additional course resources that support both independent learning and parent oversight. Parents can monitor performance without additional grading or record-keeping.
Because the course is self-paced, teens can spend additional time on challenging concepts or move more quickly through familiar material. Twelve months of access gives families the flexibility to adapt the course to their homeschool schedule.
For teens preparing for precalculus, calculus, physics, engineering, and other STEM fields, Thinkwell's Trigonometry provides a strong foundation in mathematical reasoning, problem-solving, and advanced mathematics.
Thinkwell's Trigonometry with Professor Edward Burger
Thinkwell's Trigonometry homeschool course has engaging online video lessons and step-by-step exercises that teach you what you'll need to be successful in Calculus. The Trigonometry curriculum covers trig functions, identities, ratios, and more. Instead of trying to learn what you need from an old-fashioned textbook, you can watch easy-to-understand trigonometry videos.
Thinkwell's award-winning math teacher, Edward Burger, can explain and demonstrate trig clearly to anyone, so trigonometry basics are easy to understand and remember. Professor Burger shares the tricks and tips so your students will remember them when they begin calculus.
Thinkwell's Trigonometry Table of Contents
1. Algebraic Prerequisites- 1.1 Graphing Basics
- 1.1.1 Using the Cartesian System
- 1.1.2 Thinking Visually
- 1.2 Relationships between Two Points
- 1.2.1 Finding the Distance between Two Points
- 1.2.2 Finding the Second Endpoint of a Segment
- 1.3 Relationships among Three Points
- 1.3.1 Collinearity and Distance
- 1.3.2 Triangles
- 1.4 Circles
- 1.4.1 Finding the Center-Radius Form of the Equation of a Circle
- 1.4.2 Decoding the Circle Formula
- 1.4.3 Finding the Center and Radius of a Circle
- 1.4.4 Solving Word Problems Involving Circles
- 1.5 Graphing Equations
- 1.5.1 Graphing Equations by Locating Points
- 1.5.2 Finding the x- and y-Intercepts of an Equation
- 1.6 Function Basics
- 1.6.1 Functions and the Vertical Line Test
- 1.6.2 Identifying Functions
- 1.6.3 Function Notation and Finding Function Values
- 1.7 Working with Functions
- 1.7.1 Determining Intervals Over Which a Function Is Increasing
- 1.7.2 Evaluating Piecewise-Defined Functions for Given Values
- 1.7.3 Solving Word Problems Involving Functions
- 1.8 Function Domain and Range
- 1.8.1 Finding the Domain and Range of a Function
- 1.8.2 Domain and Range: One Explicit Example
- 1.8.3 Satisfying the Domain of a Function
- 1.9 Linear Functions: Slope
- 1.9.1 An Introduction to Slope
- 1.9.2 Finding the Slope of a Line Given Two Points
- 1.9.3 Interpreting Slope from a Graph
- 1.9.4 Graphing a Line Using Point and Slope
- 1.10 Equations of a Line
- 1.10.1 Writing an Equation in Slope-Intercept Form
- 1.10.2 Writing an Equation Given Two Points
- 1.10.3 Writing an Equation in Point-Slope Form
- 1.10.4 Matching a Slope-Intercept Equation with Its Graph
- 1.10.5 Slope for Parallel and Perpendicular Lines
- 1.11 Graphing Functions
- 1.11.1 Graphing Some Important Functions
- 1.11.2 Graphing Piecewise-Defined Functions
- 1.11.3 Matching Equations with Their Graphs
- 1.12 Manipulating Graphs: Shifts and Stretches
- 1.12.1 Shifting Curves along Axes
- 1.12.2 Shifting or Translating Curves along Axes
- 1.12.3 Stretching a Graph
- 1.12.4 Graphing Quadratics Using Patterns
- 1.13 Manipulating Graphs: Symmetry and Reflections
- 1.13.1 Determining Symmetry
- 1.13.2 Reflections
- 1.13.3 Reflecting Specific Functions
- 1.14 Quadratic Functions: Basics
- 1.14.1 Deconstructing the Graph of a Quadratic Function
- 1.14.2 Nice-Looking Parabolas
- 1.14.3 Using Discriminants to Graph Parabolas
- 1.14.4 Maximum Height in the Real World
- 1.15 Quadratic Functions: The Vertex
- 1.15.1 Finding the Vertex by Completing the Square
- 1.15.2 Using the Vertex to Write the Quadratic Equation
- 1.15.3 Finding the Maximum or Minimum of a Quadratic
- 1.15.4 Graphing Parabolas
- 1.16 Composite Functions
- 1.16.1 Using Operations on Functions
- 1.16.2 Composite Functions
- 1.16.3 Components of Composite Functions
- 1.16.4 Finding Functions That Form a Given Composite
- 1.16.5 Finding the Difference Quotient of a Function
- 1.16.6 Calculating the Average Rate of Change
- 1.17 Rational Functions
- 1.17.1 Understanding Rational Functions
- 1.17.2 Basic Rational Functions
- 1.18 Graphing Rational Functions
- 1.18.1 Vertical Asymptotes
- 1.18.2 Horizontal Asymptotes
- 1.18.3 Graphing Rational Functions
- 1.18.4 Graphing Rational Functions: More Examples
- 1.18.5 Oblique Asymptotes
- 1.18.6 Oblique Asymptotes: Another Example
- 1.19 Function Inverses
- 1.19.1 Understanding Inverse Functions
- 1.19.2 The Horizontal Line Test
- 1.19.3 Are Two Functions Inverses of Each Other?
- 1.19.4 Graphing the Inverse
- 1.20 Finding Function Inverses
- 1.20.1 Finding the Inverse of a Function
- 1.20.2 Finding the Inverse of a Function with Higher Powers
- 2.1 Angles and Radian Measure
- 2.1.1 Finding the Quadrant in Which an Angle Lies
- 2.1.2 Finding Coterminal Angles
- 2.1.3 Finding the Complement and Supplement of an Angle
- 2.1.4 Converting between Degrees and Radians
- 2.1.5 Using the Arc Length Formula
- 2.2 Right Angle Trigonometry
- 2.2.1 An Introduction to the Trigonometric Functions
- 2.2.2 Evaluating Trigonometric Functions for an Angle in a Right Triangle
- 2.2.3 Finding an Angle Given the Value of a Trigonometric Function
- 2.2.4 Using Trigonometric Functions to Find Unknown Sides of Right Triangles
- 2.2.5 Finding the Height of a Building
- 2.3 The Trigonometric Functions
- 2.3.1 Evaluating Trigonometric Functions for an Angle in the Coordinate Plane
- 2.3.2 Evaluating Trigonometric Functions Using the Reference Angle
- 2.3.3 Finding the Value of Trigonometric Functions Given Information about the Values of Other Trigonometric Functions
- 2.3.4 Trigonometric Functions of Important Angles
- 2.4 Graphing Sine and Cosine Functions
- 2.4.1 An Introduction to the Graphs of Sine and Cosine Functions
- 2.4.2 Graphing Sine or Cosine Functions with Different Coefficients
- 2.4.3 Finding Maximum and Minimum Values and Zeros of Sine and Cosine
- 2.4.4 Solving Word Problems Involving Sine or Cosine Functions
- 2.5 Graphing Sine and Cosine Functions with Vertical and Horizontal Shifts
- 2.5.1 Graphing Sine and Cosine Functions with Phase Shifts
- 2.5.2 Fancy Graphing: Changes in Period, Amplitude, Vertical Shift, and Phase Shift
- 2.6 Graphing Other Trigonometric Functions
- 2.6.1 Graphing the Tangent, Secant, Cosecant, and Cotangent Functions
- 2.6.2 Fancy Graphing: Tangent, Secant, Cosecant, and Cotangent
- 2.6.3 Identifying a Trigonometric Function from its Graph
- 2.7 Inverse Trigonometric Functions
- 2.7.1 An Introduction to Inverse Trigonometric Functions
- 2.7.2 Evaluating Inverse Trigonometric Functions
- 2.7.3 Solving an Equation Involving an Inverse Trigonometric Function
- 2.7.4 Evaluating the Composition of a Trigonometric Function and Its Inverse
- 2.7.5 Applying Trigonometric Functions: Is He Speeding?
- 3.1 Basic Trigonometric Identities
- 3.1.1 Fundamental Trigonometric Identities
- 3.1.2 Finding All Function Values
- 3.2 Simplifying Trigonometric Expressions
- 3.2.1 Simplifying a Trigonometric Expression Using Trigonometric Identities
- 3.2.2 Simplifying Trigonometric Expressions Involving Fractions
- 3.2.3 Simplifying Products of Binomials Involving Trigonometric Functions
- 3.2.4 Factoring Trigonometric Expressions
- 3.2.5 Determining Whether a Trigonometric Function Is Odd, Even, or Neither
- 3.3 Proving Trigonometric Identities
- 3.3.1 Proving an Identity
- 3.3.2 Proving an Identity: Other Examples
- 3.4 Solving Trigonometric Equations
- 3.4.1 Solving Trigonometric Equations
- 3.4.2 Solving Trigonometric Equations by Factoring
- 3.4.3 Solving Trigonometric Equations with Coefficients in the Argument
- 3.4.4 Solving Trigonometric Equations Using the Quadratic Formula
- 3.4.5 Solving Word Problems Involving Trigonometric Equations
- 3.5 The Sum and Difference Identities
- 3.5.1 Identities for Sums and Differences of Angles
- 3.5.2 Using Sum and Difference Identities
- 3.5.3 Using Sum and Difference Identities to Simplify an Expression
- 3.6 Double-Angle Identities
- 3.6.1 Confirming a Double-Angle Identity
- 3.6.2 Using Double-Angle Identities
- 3.6.3 Solving Word Problems Involving Multiple-Angle Identities
- 3.7 Other Advanced Identities
- 3.7.1 Using a Cofunction Identity
- 3.7.2 Using a Power-Reducing Identity
- 3.7.3 Using Half-Angle Identities to Solve a Trigonometric Equation
- 4.1 The Law of Sines
- 4.1.1 The Law of Sines
- 4.1.2 Solving a Triangle Given Two Sides and One Angle
- 4.1.3 Solving a Triangle (SAS): Another Example
- 4.1.4 The Law of Sines: An Application
- 4.2 The Law of Cosines
- 4.2.1 The Law of Cosines
- 4.2.2 The Law of Cosines (SSS)
- 4.2.3 The Law of Cosines (SAS): An Application
- 4.2.4 Heron's Formula
- 4.3 Vector Basics
- 4.3.1 An Introduction to Vectors
- 4.3.2 Finding the Magnitude and Direction of a Vector
- 4.3.3 Vector Addition and Scalar Multiplication
- 4.4 Components of Vectors and Unit Vectors
- 4.4.1 Finding the Components of a Vector
- 4.4.2 Finding a Unit Vector
- 4.4.3 Solving Word Problems Involving Velocity or Forces
- 5.1 Complex Numbers
- 5.1.1 Introducing and Writing Complex Numbers
- 5.1.2 Rewriting Powers of i
- 5.1.3 Adding and Subtracting Complex Numbers
- 5.1.4 Multiplying Complex Numbers
- 5.1.5 Dividing Complex Numbers
- 5.2 Complex Numbers in Trigonometric Form
- 5.2.1 Graphing a Complex Number and Finding Its Absolute Value
- 5.2.2 Expressing a Complex Number in Trigonometric or Polar Form
- 5.2.3 Multiplying and Dividing Complex Numbers in Trigonometric or Polar Form
- 5.3 Powers and Roots of Complex Numbers
- 5.3.1 Using DeMoivre's Theorem to Raise a Complex Number to a Power
- 5.3.2 Roots of Complex Numbers
- 5.3.3 More Roots of Complex Numbers
- 5.3.4 Roots of Unity
- 5.4 Polar Coordinates
- 5.4.1 An Introduction to Polar Coordinates
- 5.4.2 Converting between Polar and Rectangular Coordinates
- 5.4.3 Converting between Polar and Rectangular Equations
- 5.4.4 Graphing Simple Polar Equations
- 5.4.5 Graphing Special Polar Equations
- 6.1 Exponential Functions
- 6.1.1 An Introduction to Exponential Functions
- 6.1.2 Graphing Exponential Functions: Useful Patterns
- 6.1.3 Graphing Exponential Functions: More Examples
- 6.2 Applying Exponential Functions
- 6.2.1 Using Properties of Exponents to Solve Exponential Equations
- 6.2.2 Finding Present Value and Future Value
- 6.2.3 Finding an Interest Rate to Match Given Goals
- 6.3 The Number e
- 6.3.1 e
- 6.3.2 Applying Exponential Functions
- 6.4 Logarithmic Functions
- 6.4.1 An Introduction to Logarithmic Functions
- 6.4.2 Converting between Exponential and Logarithmic Functions
- 6.5 Solving Logarithmic Functions
- 6.5.1 Finding the Value of a Logarithmic Function
- 6.5.2 Solving for x in Logarithmic Equations
- 6.5.3 Graphing Logarithmic Functions
- 6.5.4 Matching Logarithmic Functions with Their Graphs
- 6.6 Properties of Logarithms
- 6.6.1 Properties of Logarithms
- 6.6.2 Expanding a Logarithmic Expression Using Properties
- 6.6.3 Combining Logarithmic Expressions
- 6.7 Evaluating Logarithms
- 6.7.1 Evaluating Logarithmic Functions Using a Calculator
- 6.7.2 Using the Change of Base Formula
- 6.8 Applying Logarithmic Functions
- 6.8.1 The Richter Scale
- 6.8.2 The Distance Modulus Formula
- 6.9 Solving Exponential and Logarithmic Equations
- 6.9.1 Solving Exponential Equations
- 6.9.2 Solving Logarithmic Equations
- 6.9.3 Solving Equations with Logarithmic Exponents
- 6.10 Applying Exponents and Logarithms
- 6.10.1 Compound Interest
- 6.10.2 Predicting Change
- 6.11 Word Problems Involving Exponential Growth and Decay
- 6.11.1 An Introduction to Exponential Growth and Decay
- 6.11.2 Half-Life
- 6.11.3 Newton's Law of Cooling
- 6.11.4 Continuously Compounded Interest
- 7.1 Conic Sections: Parabolas
- 7.1.1 An Introduction to Conic Sections
- 7.1.2 An Introduction to Parabolas
- 7.1.3 Determining Information about a Parabola from Its Equation
- 7.1.4 Writing an Equation for a Parabola
- 7.2 Conic Sections: Ellipses
- 7.2.1 An Introduction to Ellipses
- 7.2.2 Finding the Equation for an Ellipse
- 7.2.3 Applying Ellipses: Satellites
- 7.2.4 The Eccentricity of an Ellipse
- 7.3 Conic Sections: Hyperbolas
- 7.3.1 An Introduction to Hyperbolas
- 7.3.2 Finding the Equation for a Hyperbola
- 7.3.3 Applying Hyperbolas: Navigation
- 7.4 Conic Sections
- 7.4.1 Identifying a Conic
- 7.4.2 Name That Conic
- 7.4.3 Rotation of Axes
- 7.4.4 Rotating Conics
- Video Lessons: 195 engaging 5-10 minute lesson videos
- Lesson Plan: Detailed, 36-week lesson plan and schedule
- Assessments: Automatically graded exercises and tests
- Notes & Sample Problems: Illustrated course notes, sample problems & solutions
Course Overview:
- What You Get:
- 12-month, online subscription to our complete Trigonometry course
- 36-week, day-by-day
- 190+ course lessons, each with a streaming video
- Automatically graded drill-and-practice exercises with step-by-step answer feedback
- Sample problems and solutions
- Chapter & Practice tests, a Midterm & Final Exam
- Animated interactivities....and more!
- How It Works
- Create an account username and password which will give you access to the online Trigonometry course section
- Activate your 12-month subscription when you're ready
- Login to the course website to access the online course materials, including streaming video lessons, exercises, quizzes, tests, and more
- Access your course anytime, anywhere, from any device
- Your work is automatically tracked and updated in real-time
- Grade reports and certificates of completion are available at request
Publisher: Thinkwell Homeschool Corporation
Age Recommendation: 14+
Grade Recommendation: 10th+
Faith-Based: No
Consumable: Yes
Subscription Info: 1-year subscription
System Requirements: Device with internet access
Format: Online course
Find answers to the most frequently asked questions about this product below:
Your student watches a 5-10 minute online video lesson, completes the automatically graded exercises for the topic with instant correct-answer feedback, then moves on to the next lesson! The courses are self-paced, or you can use the daily lesson plans. Just like a textbook, you can choose where to start and end, or follow the entire course.
A typical sequence of secondary math courses completed by a college-bound student is: Grade 6 Math > Grade 7 Math > Grade 8 Math > Algebra 1 > Geometry > Algebra 2 > Precalculus. For students looking to include Calculus as part of their high school curriculum and are able to complete Grade 7 Math in 6th grade, the sequence can be: Grade 7 Math > Prealgebra > Algebra 1 > Geometry > Algebra 2 > Precalculus > Calculus.
The pace of your course is up to you, but most college students will schedule one semester.
The course grade is calculated this way: Chapter Tests 33.3%, Midterm: 33.3%, Final: 33.3%.
Yes, there's a final grade report print option in the My Grades section.
Yes, but completing the exercises online provides immediate correct answer feedback and automatic scoring, so we recommend answering the exercises online.
Thinkwell's Trigonometry is carefully constructed to build on previous knowledge, reinforcing key concepts every step of the way. It is not only a reflection of empirically effective instruction, but also reflects Dr Burger’s philosophies learned over a career of teaching mathematics, emphasizing a solid foundation that addresses why students need to learn certain concepts. Finally, Thinkwell Trigonometry is intentionally designed to work for a wide variety of learning styles.
It starts when you're ready. You can have instant access to your online subscription when you purchase online, or you can purchase now and start later.
Yes, but it is more commonly taught in high school.
Some states set standards for what topics should be taught in a particular course. Thinkwell does not have a course version for each state. Instead, the course is built to national standards to be inclusive of all states. Websites such as www.achieve.org can help you determine your state's standards.
The courses are designed and licensed to accommodate one student per username and password; additional students need to purchase online access. This allows parents to keep track of each student's progress and grades.
Thinkwell courses track everything your student does. When logged in, your student can click "My Grades" to see their progress.
The exercises are multiple choice and they are graded automatically with correct answer solutions.
Generally, only schools can award credits, and Thinkwell is not a school. We can provide you with a certificate of completion and a grade report. However, if you’re pursuing credit with a particular school or institution, it might be helpful to know that Thinkwell math courses are accredited by the Western Association of Schools and Colleges (WASC) as a Supplementary Education Program. For California students, Thinkwell is also an approved A-G online publisher.
WASC Accreditation
Thinkwell has been granted accreditation as a Supplementary Education Provider by the Accrediting Commission for Schools, Western Association of Schools and Colleges (WASC) for our online courses. The WASC accreditation is a testimony to the dedication we have to high-quality teaching and learning.
WASC accreditation demonstrates:
•Thinkwell is substantially accomplishing its stated purposes and functions identified as appropriate for an institution of its type, and
•Thinkwell is meeting an acceptable level of quality in accordance with the WASC criteria adopted by the Accrediting Commission.WASC Accreditation
Thinkwell has been granted accreditation as a Supplementary Education Provider by the Accrediting Commission for Schools, Western Association of Schools and Colleges (WASC) for our online courses. The WASC accreditation is a testimony to the dedication we have to high-quality teaching and learning.
WASC accreditation demonstrates:
•Thinkwell is substantially accomplishing its stated purposes and functions identified as appropriate for an institution of its type, and
•Thinkwell is meeting an acceptable level of quality in accordance with the WASC criteria adopted by the Accrediting Commission.
A – G Approved Courses
A-G courses are a series of high school classes that students are required to successfully complete to be eligible for admission to the California State University and University of California systems. The goal of A-G curriculum is to ensure students have attained core subject knowledge that will fully and effectively prepare them for college.
Thinkwell is proud to be an approved A-G online publisher. (view the directory of CA charter schools). For California students seeking credit, it is critical that the family/student communicate with their school prior to enrolling in a Thinkwell course to confirm your school’s agreement to provide credit via a Thinkwell course. Specific instructions for California schools can be found on the University of California
Thinkwell Courses Recognized as UC A–G Approved
- Algebra 1 (Thinkwell) — fulfills C (Mathematics) requirement
- Algebra 2 (Thinkwell) — fulfills C (Mathematics) requirement
- Geometry (Thinkwell) — fulfills C (Mathematics) requirement
- Pre-Calculus (Thinkwell) — fulfills C (Mathematics) requirement
- Trigonometry (Thinkwell) — fulfills C (Mathematics) requirement
- Calculus (Thinkwell) — fulfills C (Mathematics) requirement
Getting Credit for Thinkwell Courses
Since Thinkwell is not a school, we can not grant course credit; however, our accreditation status makes it easy for accredited schools to issue credit for a Thinkwell course. With WASC accreditation, homeschooling parents can have confidence about the rigor and completeness of our course materials. Note: WASC accreditation does not indicate that your school will necessarily accept a Thinkwell course for credit.
If you are seeking credit from a school towards a degree, it is critical that you communicate with your school prior to enrolling in a Thinkwell course to confirm your school’s agreement to provide credit via a Thinkwell course.


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