Question

3sin(11П+α)+cos(15/П-α)

Answer 1

$3Sin(11\pi+\alpha)+Cos(\frac{15\pi }{2}-\alpha)=3Sin(2\pi*5+(\pi +\alpha))+Cos(2\pi*3+(\frac{3\pi }{2} -\alpha ))=3Sin(\pi+\alpha)+Cos(\frac{3\pi }{2}-\alpha)=-3Sin\alpha-Sin\alpha=-4Sin\alpha$