Math 25: College Trigonometry
The Adobe Reader
To use the textbook and Optimath system in this course, you must have properly installed and configured the Adobe Reader on your computer. You will need to download a free copy of the Acrobat Reader to read them. Click the following icon to obtain a free copy of the Acrobat Reader.
It is important that you have the most current version of the Acrobat Reader that your system will allow. The above links will take you to the Adobe site. The Adobe site will analyze your system, but you may be asked to choose the appropriate version of the reader for your system. If this happens, carefully select the appropriate version of the reader for your system.
- If you use a Windows PC, download the Adobe Reader software using the link above. Then run the Adobe Reader installer. When you are asked if you want Adobe Reader to be the default pdf reader, answer "YES".
- If you use a Macintosh, please follow these installation instructions for the Adobe Reader.
At College of the Redwoods, Math 25 is the course number for our College Trigonometry course. College Trigonometry is a transfer-level math course needed for preparation for the calculus series (Math 50A-B-C). Math 30 (College Algebra) and Math 25 together constitute what is often referred to as "Precalculus". Most students take Math 30 before Math 25, but these two courses may be taken in either order or at the same time.
Prerequisites: Grade of C or better in Math 120 (Intermediate Algebra) or equivalent, or an appropriate score on the math placement exam.
Course Description: A study of trigonometric functions, radian measure, solution of right triangles, graphs of the trigonometric functions, inverse trigonometric functions, trigonometric identities and equations, laws of sines and cosines, solution of oblique triangles, polar coordinates, complex numbers in trigonometric form, De Moivre’s theorem, and conic sections.
Student Information and Help Resources
- Textbook: The current textbook for the course is Algebra and Trigonometry (7th edition), by Sullivan, published by Prentice Hall, ISBN #0131430734.
This book can be used for both Math 30 and Math 25.
A limited number of textbooks are available on loan from the library. The textbook can also be purchased very inexpensively from various online book sellers.
• Student Solutions Manual for the 7th edition, ISBN #0131430793
• Alternatively, you can purchase the Student Study Pack for the 7th edition (ISBN #0131631837), which contains both the Student Solutions Manual and the CD Lecture Series
Alternate version: If you have trouble finding the 7th edition of the textbook, then you can purchase the 8th edition instead. The 8th edition and its corresponding ancillaries can also be purchased very inexpensively from various online book sellers.
- Note: The 8th edition textbook combined with the Student Study Pack for the 8th edition (which contains the Student Solutions Manual) is also available at the CR bookstore (ISBN #0136150667). However, it will cost much more than a copy purchased online.
- Textbook Correlation Guides:
- Graphing Calculator: Students are required to use a graphing calculator in the Math 25 course. Students can rent a calculator for the semester for $20. Instructions are available at the following link:
- Math Lab: Math 52 is the Math Lab course for Math 25 students.
- OPTIMATH is our locally-developed online practice and testing system. The portal for OPTIMATH is
For information on how to get started, see the
Introduction to OPTIMATH.
Even if your instructor does not use OPTIMATH as a formal part of the course, your can still access the following online practice exercises: