cotx = căn 3
Cotx +cot2x =0
Cot3x =0
Cot^2 x - cotx=0
Cot4x =1
tan3x=1tan2x=tanxtan^2x-căn3 tanx=03tan^2x + 2căn3 tanx + 1 =0tanx.tan5x=0
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