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�) 4sin^2(1�)cos^2(1�)-cos^2(2�);

�) 16sin^2(3�)cos^2(3�)cos^2(6�);

�) (sin(10�)+sin(80�))(cos(80�)-cos(10�));

�) (cos(5�)+cos(95�))(sin(85�)+sin(175�)).

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