求证:sin(2x+y)/sinx-2cos(x+y)=siny/sinx
来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/05/16 08:36:05
求证:sin(2x+y)/sinx-2cos(x+y)=siny/sinx
(2)已知5siny=sin(2x+y),求证:tan(x+y)=3/2 tanx
(2)已知5siny=sin(2x+y),求证:tan(x+y)=3/2 tanx
把5siny=sin(2x+y)变为5sin[(x+y)-x]=sin[(x+y)+x],把其中的(x+y),看成一个整体,上式即变为4sin(x+y)cosx=6cos(x+y)sinx,再把式子的左右两边变换为sin(x+y)/cos(x+y)=3/2sinx/cosx,即tan(x+y)=3/2 tanx
求证:sin(2x+y)/sinx-2cos(x+y)=siny/sinx
求证sinx+siny=2sin(x+y)/2*cos(x-y)/2
求证|sinx-siny|=|2sin[(x-y)/2]cos[(x+y)/2]|
求证:sin(x-y)/(sinx-siny)=cos[(x-y)/2]/cos[(x+y)/2]
证明 [sin(2x+y)/sinx]-2cos(x+y)=siny/sinx
请问,如何证明sinx+siny=2*sin(x+y/2)*cos(x-y/2)
为什么sin(x+y) - sinx = 2cos(x+y/2)siny/2
两角和差公式sinx-siny=2sin[(x-y)/2]cos[(x+y)/2]推导.
证明sin(x+y)sin(x-y)=sinx-siny
证明sinx+siny+sinz-sin(x+y+z)=4sin((x+y)/2)sin((x+y)/2)sin((x+
证明sin(x+y)sin(x-y)=(sinx)^2-(siny)^2.
证明cosx(cosx-cosy)+sinx(sinx-siny)=2sin(x-y)/2