Question

cos(π/3+α)+sin(π/6+α)=?

cos(π/3+α)+sin(π/6+α)=?

过程，谢谢

Answer 1

cos(π/3+α)+sin(π/6+α)=cos(π/3+α)+cos[π/2-(π/6+α)]
=cos(π/3+α)+cos(π/3-α)
=cosπ/3casα-sinαsinπ/3+cosπ/3casα+sinαsinπ/3
=2cosπ/3casα=casα
今天立春,祝你新春快乐!

Answer 2

cos阿尔发

Answer 3

原式=1/2cosa-根号3/2sina+1/2cosa+根号3/2sina
=cosa