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• 2cos 2x = 0 cos 2x = 0 2x = pi/2 + n* pi for the classic answer (that's, extraordinary values of npi/2, the position n is an integer) dividing by utilizing 2: x = pi/4 + npi/2 or, x = pi/4 (a million + 2n) <== established answer in case you only …

  in 2cos^2(x) - cos(x) = 0? Comment by isla-brown_60b6f7e399a5c June 2021