f(x,y)=(sin(x) x)*(sin(y) y)的MATLAB-搜答案-智慧作业帮

函数f（x)=sin(3x+y)是偶函数,则f(-x)=sin(-3x+y)=f(x)=sin(3x+y)由正弦函数的性质sin(π-x)=sinx及周期性可得(-3x+y)+(3x+y)=π+2kπ

sin^2(x-y)+sin^2(y-z)+sin^2(z-x)=[1-cos2(x-y)+1-cos2(y-z)+1-cos2(z-x)]/2=3/2-[(cos2xcos2y+sin2xsin2y

f(x)=|sinx+cosx+tanx+cotx+secx+cscx|=|(sinx+cscx)+(cosx+secx)+(tanx+cotx)|∵sinx+cscx≥2√(sinx·cscx)=2

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)=（si

y'=f'(sin²x)*(sin²x)'+f'(cos²x)*(cos²x)'=f'(sin²x)*(2sinxcos)+f'(cos²x

见图,复合函数求导.

dy/dx=2xf'(x²))cosf(x²)再问：没有过程吗？再答：复合函数求导法则

这是个函数句柄@(x,y)表示未知数是x和ypunct-Functionhandlecreation@@在匿名函数中表示函数句柄例如ln(x),在matlab中是没有定义的,正确表示是log(x);但

y'=f'(sinx^2)*cosx^2*2x-f'(cosx^2)*sinx^2*2x

dy/dx=y'=f'[2x/(x-1)]*[[2x/(x-1)]'=sin[2x/(x-1)]²*-2/(x-1)²=-2sin[2x/(x-1)]²/(x-1)

设x0所以f(-x)=sin2(-x)+cos(-x)=-sin2x+cosx因为f(x)为奇函数,所以f(-x)=-f(x)得f(x)=-f(-x)=sin2x-cosx(x

设函数f（x,y)=sin(x+y),那么f(0,xy）=(sinxy)应该是sin0+sinsy=0+sinxy=sinxy再问：limsinxy\2x=()补充x→0，y→3另外一道题

dy/dx=cos{f[sinf(x)]}*{f[sinf(x)]}'=cos{f[sinf(x)]}*f‘[sinf(x)]*[sinf(x)]’=cos{f[sinf(x)]}*f‘[sinf(x

f(x)=cos(3x)*cos(2x)+sin(3x)*sin(2x)=cos(3x-2x)=cosxf'(x)=-sinx

已知f(x)=sin

（根号2＋根号6）÷4再问：如何做的？？？？？？？？？？谢谢

y'sin(y/x)-y/x*sin(y/x)+1=0令y/x=u,则y'=u+xu'所以(u+xu')sinu-usinu+1=0xu'sinu+1=0-sinudu=dx/x两边积分：cosu=l

求导 y=sin(x^x)

(x^x)'=(1+lnx)x^x所以y'=(1+lnx)x^xcos(x^x)

y'=f'(sin^2x)*(sin^2x)'=g(sin^2x)*2sinxcosx

f(x)=sin2(x+y/2)由于sin2x对称轴为π/4+kπ/2;故x+y/2=π/4+kπ/2x=π/4+kπ/2-y/2;将x=x=π/8代入,得y=π/4+kπ,根据y的范围可知：y=-3

再问：谢谢了写的清楚明白