Trigonometric Identities

Proving trigonometric identities requires perseverance, a willingness to make mistakes, being able to leave a question and come back to it and a positive mindset.

 

I first wrote out some things we knew.

Solving Trigonometric Equations (a third time)

A review of the compound angle formulas, the double angle formulas and the Pythagorean identity.

All the following questions required to find theta (or x or the angle) between 0 radians and 2pi radians.

First a linear example.

Double Angle Formulas

 

Started by using the compound angle formulas and replaced the second angle so it would be equal to the first. By doing this we were able to generate the double angle formulas for sin2A, cos2A, and tan2A. Here is some work from various groups.

 

Compound Trigonometric Formulas

 

Creating the Trigonometric Equalities Between Different Angles

This post shows the relationship between theta, pi - theta, pi + theta, 2pi - theta, pi/2 - theta,
pi/2 + theta, 3pi/2 - theta, 3pi/2 + theta.

Review for test 2

 

War with Radians

A little review of radians and a review of the special triangles from last year only this year with radians.