sin113cos323+cos247cos307=

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по формулам привидения:sin113°=sin(180°-67°)=sin67°cos323°=cos(270°+53°)=sin53°cos247°=cos(180°+67°)=-cos67°cos307°=cos(360°-53°)=cos53°sin113° *cos323°+cos247° *cos307°==sin67° *sin53°-cos67° *cos53°=-(cos67° *cos53°-sin67° *cos53°)-cos(67°+53°)=-cos120°=-cos(180°-60°)=-(-cos60°)=cos60°=1/2=0,5