函数倍角公式总结

  sin(A+B)=sinAcosB+cosAsinB   sin(A-B)=sinAcosB-cosAsinB?   cos(A+B)=cosAcosB-sinAsinB   cos(A-B)=cosAcosB+sinAsinB   tan(A+B)=(tanA+tanB)/(1-tanAtanB)   tan(A-B)=(tanA-tanB)/(1+tanAtanB)   cot(A+B)=