Question

sin(a+b)=?

sin(a+b)=?
这个公式是等于什么
sin(a-b)=?
cos(a+b)=?
cos(a-b)=?

Answer 1

两角和公式
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) = (cotAcotB-1)/(cotB+cotA) �
cot(A-B) = (cotAcotB+1)/(cotB-cotA)

Answer 2

sin(a+b)=sinacosb+cosasinb

sin(a-b)=sinacosb-cosasinb

cos(a+b)=cosacosb-sinasinb

cos(a-b)=cosacosb+sinasinb

Answer 3

sin(a+b)=sinacosb+sinbcosa
sin(a-b)=sinacosb-sinbcosa
cos(a+b)=cosacosb-sinasinb
cos(a-b)=cosacosb+sinasinb

Answer 4

sin(a+b)=sinacosb+sinbcosa
sin(a-b)=sinacosb-sinbcosa
cos(a+b)=cosacosb-sinasinb
cos(a-b)=cosacosb+sinasinb