Lesson 5.3
         Solving 
     Trigonometric Equations
                    Solving 
           Trigonometric Equations
        To solve trigonometric equations:
        Use standard algebraic techniques learned in Algebra II.
         Look for factoring and collecting like terms.
         Isolate the trig function in the equation.
         Use the inverse trig functions to assist in determining 
         solutions.
                      Solving 
            Trigonometric Equations
               For all problems, 
             The solution interval
                     Will be
                     [0, 2π)
    You are responsible for checking your solutions back into the original problem!
                                               Solving 
                          Trigonometric Equations
                 Solve:    2cosx−1=0
                 Step 1:  Isosolate cos x using algebraic skills.
                           2cosx=1
                           cosx= 12
                 Step 2:  Determine in which quadrants cosine is positive.  Use the inverse
                 function to assist by finding the angle in Quad I first.  Then use that angle
                 as the reference angle for the other quadrant(s).
                                 QI QIV                   Note:  cosine is positive in 
                                 π 5π                     Quad I and Quad IV.
                            x =     ,                     Note:  The reference angle is π/3.
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