関連ワード:  1 cos 2 2x is equal to    sin 3x 1 2 cos 2x is equal to    1 cos 2x is equal to 2 sin square x    1 cos 2x x 2 is equal to    1 cos2x 2 is equal to    cos inverse 1 2x 2 is equal to    1 2 sin x 2 cos 2x 1 is equal to    cos 3x 2 cos 2x 1 is equal to    if 2 cos 2x 1 then x is equal to    cos 2x is equal to 1 minus 2 sin square x