1 √x^2 y^2arctany xd-搜答案-搜搜考试网

两边对x求导得1/[1+(y/x)^2]*(y/x)'=1/[ln(x^2+y^2)]*[ln(x^2+y^2)]'1/[1+(y/x)^2]*(y'x-y)/x^2=1/[2ln(x^2+y^2)]

F(x,y)=A(B+arctanx/2)(C+arctany/3)F(-∞,-∞)=A(B-π/2)(C-π/2)=0F(-∞,+∞)=A(B-π/2)(C+π/2)=0F(+∞,-∞)=A(B+π

第一题上面已有朋友回答第二题可以先化简得：y'＝y^2\（－x+2xy+y^2）,也可记为dy\dx=y^2\（－x+2xy+y^2）,则dx\dy=（－x+2xy+y^2）\y^2,化简得：dx\d

1/2*ln(x^2+y^2)=arctany/x两边对x求导,得1/2*1/(x^2+y^2)*(2x+2y*y')=1/[1+(y/x)^2]*(y'*x-y)/x^2化简得y'=(x+y)/(x

y+arctany-x=0dy/dx+1/(1+y^2)dy/dx-1=0dy/dx(1+1/(1+y^2)=1dy/dx=(1+y^2)/(2+y^2)

y''=-(2+2y^2)/y

x+arctany=y两边对x求导有：1+y'/(1+y²）=y'整理得：y'=1+1/y²

设y=2arctan(y/x),求dy/dx,d²y/dx².设F(x,y)=y-2arctan(y/x)=0,则dy/dx=-(∂F/∂x)/(ͦ

1)x(x-y)(x+y)-x(x+y)^2=x((x-y)(x+y)-(x+y)^2)=x(x^2-y^2-x^2-2xy-y^2)=x(-2xy-2y^2)=-2xy(x+y)2)（2a+b)(2

答案在插图：

见图再问：不好意思啊~题目看错了，题目如图啊~

利用概率分布函数特性F(正无穷,正无穷)=1,F(负无穷,负无穷)=0,带入就是A(B+π/2)(C+π/2)=1A(B-π/2)(C-π/2)=0展开后,两式相加：ABC=1/2-(π^2)/4再问

(1)(x^2/x)-y-x-y

（1)x^2/x)-y-x-y=x-y-x-y=-2y(2)(a/a-b)-(a/a+b)-(2b^2/a^2-b^2)=a(a+b-a+b)/(a^2-b^2)-(2b^2/a^2-b^2)=2b/

1.y=arcsin(cosx)y'=[1/√（1－cos²x）](-sinx)=-sinx√（1－cos²x）/sin²x＝－|sinx|/sinx∴当sinx＞0时y

设z=arctany/x,求dz?

是(arctany)/x还是arctan(y/x)?如果是z=(arctany)/x,则∂z/∂x=-(arctany)/x²∂z/∂y=1/

利用查表或反函数求导法可求得(arctanu)'=1/(1+u^2)∴上述方程两边分别对x求导可得1+y'=y'/(1+y^2)=>(1+y^2)+(1+y^2)y'=y'=>(1+y^2)+y^2y

左右2边取正切,左边=(X+Y)/(1-XY)=右边.左边=arctan[(X+Y)/(1-XY)+Z]/[1-(X+Y)Z/(1-XY)]=arctanc(X+Y+Z-XYZ)/[1-XY-(X+Y

❶证明：tan(arctanX+arctanY)=(X+Y)/(1-XY)证明：tan(arctanx+arctany)=(tanarctanx+tanarctany)/[1-(tana

全微分吗?z=arctan(y/x)∂z/∂x=1/(1+y²/x²)*y=x²y/(x²+y²)∂z/ͦ