Cos(альфа+125гр)/sin(альфа+35гр)

[latex] \frac{cos( \alpha +125^0)}{sin( \alpha +35^0)}= \frac{cos \alpha *cos125^0-sin \alpha sin125^0}{sin \alpha cos35^0+cos \alpha *sin35^0}=\frac{cos \alpha cos(90^0+35^0)-sin \alpha *sin(90^0+35^0)}{sin \alpha cos35^0+cos \alpha sin35^0} [/latex] = [latex]\frac{cos \alpha*(-sin35^0)-sin \alpha *cos35^0}{sin \alpha cos35^0+cos \alpha sin35^0} =\frac{-(cos \alpha*sin35^0+sin \alpha *cos35^0)}{sin \alpha cos35^0+cos \alpha sin35^0} =-1[/latex]