积化弊好早和差公式:租雀
sinαsinβ=-[cos(α+β)-cos(α-β)]/2 cosαcosβ=[cos(α+β)+cos(α-β)]/2 sinαcosβ=[sin(α+β)+sin(α-β)]/袜扰2 cosαsinβ=[sin(α+β)-sin(α-β)]/2
sina+sinb=2sin[(a+b)/档春禅2]cos[(a-b)/2]
sina-sinb=2cos[(a+b)/行尘2]sin[(a-b)/2]
cosa+cosb=2cos[(a+b)/2]cos[(a-b)/森饥2]
cosa-cosb=-2sin[(a+b)/2]sin[(a-b)/2]
sinacosb=1/2*[sin(a+b)+sin(a-b)]
sinacosb=1/稿伏2*[sin(a+b)+sin(a-b)]
cosasinb=1/宽敬行慎哗2*[sin(a+b)-sin(a-b)]
cosacosb=1/2*[cos(a+b)+cos(a-b)]
sinasinb=-1/2*[cos(a+b)-cos(a-b)]