Section 7.5: Solving Trig Equations January 06, 2016

Day 2: Double Angle Identities & Erroneous Solutions

1.) 6sin2x = 6cosx 2x ≠ xto solve an

equation you must be using the same angle in each trig

function

2. cos2x + 8sin2x + sinx = 3

Section 7.5: Solving Trig Equations January 06, 2016

3. cos2x + 6cos2x + 2cosx = 2

Erroneous Solutions - solutions you get while solving that do not work in the original problem*only occurs when there is a tangent or cotangent & a quadrant angle, because the functions could be undefined at those points.*the same would be true for sec & csc at their points of discontinuity

4. sinxtanx - tanx = 0

Section 7.5: Solving Trig Equations January 06, 2016

5. 3sinxcotx - 4sinx = 0