Tangent of Theta +90

This applet uses the original geometric definition of a tangent to demonstrate the identity [math]\tan(\theta +90)=-cot\theta[/math]. It requires a bit of work on the part of students to show that the two right triangles are similar and then to set up proportions and assign signs.

 

dborkovitz

 
Resource Type
Activity
Tags
exploration  identities  tangent-function  trigonometry 
Target Group (Age)
15 – 18
Language
English (United States)
 
 
GeoGebra version
4.0
Views
2825
Contact author of resource
 
 
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