Grades 8-12 
Mathematics 
Geometry 
Standard 18

Students know the definitions of the basic
trigonometric functions defined by the
angles of a right triangle, and they also know and
are able to use elementary relationships between
them, tan(x) = sin(x)/cos(x), (sin(x))+
(cos(x))2 =1.
 
 
Resources
Lesson Plans
Assessments

Geometry Larson/Boswell/Stiff, 1995, 
D.C. Heath and Company 

Section References  

9.2 Pythagorean Theorem 

9.4 Special Right Triangles 

9.5 Trigonometric Ratios 

9.6 Extended Applications: Solving Right Triangles 

Specific Textbook   
Web Sites   

http://www.glencoe.com/  
sec/math/prealg/mathnet/   

http://www.eduplace.com/  
links/   

http://www.eduplace.com/   

http://www.hmco.com/  
college/mathematics/  
index.html   

http://www.mcdougallittell  
.com/   

http://www.hmco.com/   

http://www.SRA-4KIDS.com/   

General Math   
Reference Sites   

http://www.learner.org/  
sami/view-category.php3  
?category=math   

http://www.score.k12.ca.us/   

http://henson.austin.apple  
.com/edres/curric.shtml   

http://school.discovery.com/  
schrockguide/index.html   

http://www.EDsOasis.org/   

http://www.math.com/   

http://www.nea.org/grants/  
free.html   

http://www.wcom.com/  
marcopolo/   

http://www.udel.edu/sine/   

http://dewey.chs.chico.k12  
.ca.us/math.html   

Free Stuff   

http://www.nea.org/  
grants/free.html   

State/National Math   
Ed Organizations   

http://www.nctm.org/   

http://www.cde.ca.gov/   

Calif. Dept. of Ed. Standards, Assessment, Ed. Reference.   

Calculator Reference Site   

http://www.ti.com/  
calc/docs/calchome.html 



Previously Published Data 

1.) Students will review and use the rules of simplifying fractions. 


2.) Students will use the rules of fractions to simplify sine over cosine. 
3.) Students will learn the other trigonometric functions. 
4.) Students will apply what they know about sine, cosine, and the Pythagorean Theorem to learn the trigonometric identities.
 

Previously Published Data 

1.) Students will make posters explaining the Trigonometric identities. 


2.) Students will record in their mathematics journals the trigonometric identities. 
3.) Students will use the trigonometric ratios to find the missing sides of triangles when the angles are known. 
4.) Students will simplify trigonometric expressions using the relationship between them, such as sin x/ cos x = tan x