Books
by Rebecca Wingard-Nelson
Age: 14 and up
This self-help, step-by-step book helps students learn and practice the
trigonometric aspects of triangles in the unit circle in order to understand how to
use sine and cosine. This book breaks down these concepts and many more into
easy to follow steps, lessons, and examples for students in order for them to
really learn how trigonometry works and how to feel confident when using these
concepts.
Websites
Mathisfun.com: Introduction to Trigonometry:
http://www.mathsisfun.com/algebra/trigonometry.htmlAge: 14 and up
This helpful website is very user-friendly which allows students to get a basic understanding of how trigonometric functions work, what they represent, and how to compute with them. There are many easy to read examples that guide students through the steps, and there is even an interactive unit circle so students can get a visual representation of the circle and how the trigonometric functions work.This is a great site for students to use outside of the classroom, as well.
The Inverse Trigonometric Functions:
http://www.mathopenref.com/triginverse.html
Age: 15-16 and up
Where there are trigonometric functions, there are their inverses. The website above shows the relationship between the trig function and its inverse, and it walks the reader through the background information, how to find them using a calculator, and how to solve with them in a written problem. It is a very supportive site that the reader can follow along with, perform problems, and read helpful hints and notes when it comes to using inverses trigonometric functions in triangles.
Trigonometric Functions:
http://www.intmath.com/trigonometric-functions/trig-functions-intro.php
Ages: 14 and up
In the opening page of this site, the title is what catches the reader. The title states, "Why learn trigonometric functions..?" I think this is a great header because many students see themselves asking this question many times, too. With this site, students read the opening page, and from there, they can explore the different aspects of trigonometric functions within this chapter of text. They have the freedom to chose where they want to go and what they want to discover, and the articles are links posted below the first page of text. These sub-articles also have great hooks to catch the reader's eye!
The Six Trigonometric Functions and Reciprocal Functions:
http://www.regentsprep.org/regents/math/algtrig/ATT1/trigsix.htm
Ages: 14 and up
The trig functions,along with their reciprocals, are laid out in an opening table that is great for students to read and make flashcards of if they wish. It is very spelled out for them to understand each function's parts and the parts of their reciprocal. Between the two sets, they can read and discover the relationship that they have. There are many charts that might seem overwhelming, but there are many examples for the students to work on and see how to solve problems with the functions and their reciprocals. The examples are very detailed and help students see the set up and the solution step-by-step. At the bottom, students can see how to use their calculator in order to solve the problems.
Trigonometry Facts: Exact values of the Trigonometric Functions:
http://mathmistakes.info/facts/TrigFacts/learn/vals/sum.html
Ages: 16 and up (Students in Pre-Calculus)
With this site, students can test themselves on memorizing the values of the trigonometric functions on the unit circle where the angle and radian is presented. It is very similar to flash cards which can be very helpful for students! The user can click the link in the box to show or hide the answer to the trig function, and they can memorize all of them! This is really useful for a pre-calculus student because they are working with the unit circle, the functions, and the values on a heavy and regular basis.
Basic Trigonometric Ratios:
http://www.purplemath.com/modules/basirati.htm
Ages: 13 and up
Articles
The Tale of Unit Circle City
Ages: 15 and up
Nothing beats a classic comic strip! This story of Sine and Cosine man making sure that the city of Unit Circle remains out of harms way is a great read! This comic presents trigonometric math in a very fun and exciting way that appeals to non-math students. It does include a lot of other mathematical functions such as logs, but it is still a fun read that gets students excited about reading math while giving them mathematical information.
Sine- Trigonometry for Kids!:
http://scienceforkids.kidipede.com/math/trigonometry/sine.htm
This article presents the use of sine, sine graph, and solving for sine in triangles in a very up-beat and engaging fashion. This site presents many topics and concepts that shows their history and how it is relevant today. There are many visuals for students to read and analyze, and the article makes excellent connections to angles and students daily lives. There is also a page for cosine and tangent for students to explore!
Trigonometry Basics Study Guide:
http://www.education.com/study-help/article/trigonometry-basics/
Ages: 14 and up
A quick and simple study guide is a great resource for students to access in any subject, but especially in math. This article gives the reader an overall lesson and refresher of trigonometric functions while helping students understand the basics of them, as well. Example problems are given and students are able to follow along or complete on their own. It is a lot to practice for students to complete, but it does cover all types of questions that they could possibly see.
The Trig Functions- Overview:
http://math2.org/math/algebra/functions/trig/
Ages: 14 and up
The article in this link is very straight-forward, and it is in its simplest form an overview of trigonometric functions. It also breaks down what trigonometric functions mean, how to set them up correctly, the relationships, and a written out way of how to piece together these complex functions. There is a quite a bit of reading in this article, but if there are some students who like reading, this should be a great source for them!
The Unit Circle:
http://suite101.com/a/the-unit-circle-a64437
Ages: 15 and up
Interactives
Earth Math:
http://earthmath.kennesaw.edu/main_site/review_topics/trig_functions.htm
Inverse Sine, Cosine, and Tangent:
http://www.mathwarehouse.com/trigonometry/inverse-sine-cosine-tangent/
Ages: 14 and up/ Teachers
Trigonometric functions are very useful, and so are their inverses. This website shows how finding the inverse compares to using the interior angle sum theorem, and it demonstrates how to use both methods. This relationship can be very helpful to see, and they do a great job at showing it. It also shows videos on how to input inverses into a calculator. There are interactive example problems for students to compute, and the site provides links to an online calculator and worksheet to practice more problems.
Degrees and Radians:
http://www.mathinary.com/degrees_radians.jsp
Ages: 16 and up: Pre-Calculus students:
One important concept with trigonometric functions and the unit circle is converting between degrees and radians. Both of these measures are found on the unit circle, and there are ways to find them! With this site, the reader can briefly read what each, degrees and radians, mean and how to convert either way. At the bottom, the user can use the interactive calculator to determine how to convert from degrees to radians and radians to degrees. This site is very straight forward with the reading and concepts, but it is a very good sight for those who struggle with heavy reading.