1) 2cos<span>^2x - 1 - sinx = 0</span>
<span>2) 2sin<span>^2x - 1 + cosx = 0</span></span>
<span><span>3) 2cos^2x - 1 + sinx = 0</span></span>
<span><span>4) cos2x - cosx = 0</span></span>
<span><span>5) sinx + cosx + sin3x = 0</span></span>
<span><span>6) 2sin^2x - 5sinxcosx + 5cos^2x = 1</span></span>
<span><span>7) sqrt3cosx - sinx = 0</span></span>
<span><span>8) sqrt3cosx - sinx = 1</span></span>
<span><span>9) sin^2x + cos^2 2x + sin^2 3x = 3/2</span></span>