sin（x+y）
@太该4779：y=sin(x+y)用隐函数求导? - 作业帮
能保13217437453…… [答案] y=sin(x+y)等式两边同时对x求导, y'=cos(x+y)*(1+y');所以y'=cos(x+y)/[1-cos(x+y)] 注意y是x的函数!
@太该4779：急:sin(x+y)=sinxcosy+cosxsiny怎么证明??? -
能保13217437453…… 用三角函数的积化和差公式,sinXcosY=[sin(X+Y)+sin(X-Y)]/2 cosXsinY=[sin(X+Y)-sin(X-Y)]/2 两个式子一加,消去sin(X-Y)即可
@太该4779：如题求证sin(x+y)=sinxcosy+sinycosx急 - 作业帮
能保13217437453…… [答案] 画一单位圆,圆心为O |OA|=1,与x轴夹角为a,故A(cosa,sina) |OB|=1,与x轴夹角为b,故A(cosb,sinb) 根据向量OA点乘向量OA=|OA||OB|cos 得cos(x-y)=cosxcosy+sinysinx 然后角替换下
@太该4779：求隐函数的导数sin(x+y)=x+y - 作业帮
能保13217437453…… [答案] 实际上,还有一种取巧的方法:因为sin x = x 这个方程,只能是在x=0时成立 所以sin(x+y)=x+y,实际上就是x+y=0,所以求导变成了dy/dx=-1
@太该4779：sin(x+y)的导数 - 作业帮
能保13217437453…… [答案] (1+y')cos(x+y)
@太该4779：求y=sin(x+y)的二阶导数,详细过程谢谢 -
能保13217437453…… y= sin(x+y) y'= ( 1+ y')cos(x+y) y''=y''.cos(x+y) -(1+y')^2 .sin(x+y) =y''.cos(x+y) -(1+y').y' =y''.cos(x+y) -{ 1+ cos(x+y)/(1-cos(x+y) ] } .[cos(x+y)/[1-cos(x+y)] =y''.cos(x+y) -{ cos(x+y)/[(1-cos(x+y) ]^2 } [1-cos(x+y) ] y''=-cos(x+y)/[(1-cos(x+y) ]^2 y''=- cos(x+y)/[(1-...
@太该4779：请推导一下sin(x+y) -
能保13217437453…… sin(x+y)=sinxcosy+cosxsiny 推导过程: 首先建立直角坐标系,在直角坐标系xOy中作单位圆O,并作出角a,b,与-b,使角a的始边为Ox,交圆O于点P1,终边交圆O于点P2,角b的始边为OP2,终边交圆O于点P3,角-b的始边为OP1,终边交圆...
@太该4779：cos(x+y)=?sin(x+y)=?如题 - 作业帮
能保13217437453…… [答案] cos(x+y)=cosxcosy-sinxsiny sin(x+y)=sinxcosy+cosxsiny
@太该4779：证明sin(x+y)sin(x - y)=(sinx)^2 - (siny)^2. - 作业帮
能保13217437453…… [答案] sin(x+y)sin(x-y) =-1/2(cos(x+y+x-y)—cos(x+y-x+y)) =-1/2(cos2x—cos2y) =-1/2(1-2(sinx)^2-1+2(siny)^2) =(sinx)^2-(siny)^2
@太该4779：选择题sin(x+y)=sinx+siny,下面结论正确的是 -
能保13217437453…… 解:sin(x+y)=sinxcosy+cosxsiny小于等于sinx+siny所以A是错的 当x+y=2kπ(k∈z)时,sin(x+y)=0,而sin(2kπ-x)=-sinx,即sinx+siny=sinx+sin(2kπ-x)=sinx-sinx=0,所以B是对的,则CD均错 所以本题选B
能保13217437453…… [答案] y=sin(x+y)等式两边同时对x求导, y'=cos(x+y)*(1+y');所以y'=cos(x+y)/[1-cos(x+y)] 注意y是x的函数!
@太该4779：急:sin(x+y)=sinxcosy+cosxsiny怎么证明??? -
能保13217437453…… 用三角函数的积化和差公式,sinXcosY=[sin(X+Y)+sin(X-Y)]/2 cosXsinY=[sin(X+Y)-sin(X-Y)]/2 两个式子一加,消去sin(X-Y)即可
@太该4779：如题求证sin(x+y)=sinxcosy+sinycosx急 - 作业帮
能保13217437453…… [答案] 画一单位圆,圆心为O |OA|=1,与x轴夹角为a,故A(cosa,sina) |OB|=1,与x轴夹角为b,故A(cosb,sinb) 根据向量OA点乘向量OA=|OA||OB|cos 得cos(x-y)=cosxcosy+sinysinx 然后角替换下
@太该4779：求隐函数的导数sin(x+y)=x+y - 作业帮
能保13217437453…… [答案] 实际上,还有一种取巧的方法:因为sin x = x 这个方程,只能是在x=0时成立 所以sin(x+y)=x+y,实际上就是x+y=0,所以求导变成了dy/dx=-1
@太该4779：sin(x+y)的导数 - 作业帮
能保13217437453…… [答案] (1+y')cos(x+y)
@太该4779：求y=sin(x+y)的二阶导数,详细过程谢谢 -
能保13217437453…… y= sin(x+y) y'= ( 1+ y')cos(x+y) y''=y''.cos(x+y) -(1+y')^2 .sin(x+y) =y''.cos(x+y) -(1+y').y' =y''.cos(x+y) -{ 1+ cos(x+y)/(1-cos(x+y) ] } .[cos(x+y)/[1-cos(x+y)] =y''.cos(x+y) -{ cos(x+y)/[(1-cos(x+y) ]^2 } [1-cos(x+y) ] y''=-cos(x+y)/[(1-cos(x+y) ]^2 y''=- cos(x+y)/[(1-...
@太该4779：请推导一下sin(x+y) -
能保13217437453…… sin(x+y)=sinxcosy+cosxsiny 推导过程: 首先建立直角坐标系,在直角坐标系xOy中作单位圆O,并作出角a,b,与-b,使角a的始边为Ox,交圆O于点P1,终边交圆O于点P2,角b的始边为OP2,终边交圆O于点P3,角-b的始边为OP1,终边交圆...
@太该4779：cos(x+y)=?sin(x+y)=?如题 - 作业帮
能保13217437453…… [答案] cos(x+y)=cosxcosy-sinxsiny sin(x+y)=sinxcosy+cosxsiny
@太该4779：证明sin(x+y)sin(x - y)=(sinx)^2 - (siny)^2. - 作业帮
能保13217437453…… [答案] sin(x+y)sin(x-y) =-1/2(cos(x+y+x-y)—cos(x+y-x+y)) =-1/2(cos2x—cos2y) =-1/2(1-2(sinx)^2-1+2(siny)^2) =(sinx)^2-(siny)^2
@太该4779：选择题sin(x+y)=sinx+siny,下面结论正确的是 -
能保13217437453…… 解:sin(x+y)=sinxcosy+cosxsiny小于等于sinx+siny所以A是错的 当x+y=2kπ(k∈z)时,sin(x+y)=0,而sin(2kπ-x)=-sinx,即sinx+siny=sinx+sin(2kπ-x)=sinx-sinx=0,所以B是对的,则CD均错 所以本题选B
