Solving trigonometric equations using sum and difference identities

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Examples
Lessons
  1. Utilizing "Sum and Difference Identities" to solve:

    1. sin(x+π4)+sin(xπ4)=1,\sin (x + {\pi \over 4} ) + \sin (x - {\pi \over 4} ) = -1,
      general solution in degrees
    2. cos3xcosx+sin3xsinx=0,\cos 3x \cos x + \sin 3x \sin x =0,
      0x0 \leq x < 2π2\pi