化简[sin(a+b)-2cosasinb]/[cos(a+b)+2sinasinb]

来源：学生作业帮编辑：神马作文网作业帮分类：数学作业时间：2024/11/15 16:20:59

sin(a+b)-2cosasinb
=sinacosb+sinbcosa-2cos2sinb
=sinacosb-sinbcosa
=sin(a-b)
cos(a+b)+2sinasinb
=cosacosb-sinasinb+2sinasinb
=cosacosb+sinasinb
=cos(a-b)
所以:
[sin(a+b)-2cosasinb]/[cos(a+b)+2sinasinb]
=sin(a-b)/cos(a-b)
=tan(a-b)

sinAsinB+cosAcosB这个怎么变换!sinAcosB+cosAsinB为什么等于sin(A+B) 证明sin(a+b)=sinacosb+cosasinb sin(A+B)=sinAcosB+cosAsinB 证明cos(A+B)=cosAcosB-sinAsinB 证cos(A-B)=cosAcosB+sinAsinB cosacosb+sinasinb=cos(a-b) 一提三角函数转换题已知sinasinb=1,求cos((a+b)/2) 化简[sin(2A+B)]/sinA-2cos(A+B) sin(A+B)=sinAcosB+cosAsinB//如何证明? sin(A-B)=sinAcosB-cosAsinB怎么证明? sin(A+B) = sinAcosB+cosAsinB公式的证明过程 sin(a-b)=sinacosb-cosasinb如何推导?