设y=f(x)=arctanx,求f^n(x)-搜答案-智慧作业帮

对函数求导,令导函数值等于0,求出极值（其中arctanx求导=1/1+x22是平方）；二次求导,令导函数等于0,求出拐点,导函数值大于0,凹,小于0,凸

①首先,我们可以认为tan(π/2)=+∞,这是自然的,因此可以说arctan(+∞)=π/2第一问的π/2就是这么来的,把x、y都带成+∞,然后分布函数的意思就是x

（1）limA(B+arctanx/2)(C+arctany/2)=0-无穷limA(B+arctanx/2)(C+arctany/2)=1+无穷所以A=1/πB=π/2C=π/2(2）接下去就是求导

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

1.f(x)+f(-x)=2(arccosx+arccos-x)+arctanx+arctan-x-2pi=2pi+0-2pi=0,得证.2.arctanx+arctan1/y=arctan3tan(

记g(x)=f(x^2+sin^2x)+f(arctanx)=yg'(x)=f'(x^2+sin^2x)(2x+sin2x)+f'(arctanx)/(x2+1)dy/dx|x=0,即g'(0)代入得

解f[x]=arctanxf'[x]=1/[1+x^2]f'[0]=1不懂追问

y=f[(x-1)/(x+1)],f'(x)=arctanx^2,求dy/dx,dy两边对x求导：dy/dx=f'[(x-1)/(x+1)]*2/（x+1)^2=arctan[(x-1)/(x+1)]

令u=x+arctanx,则u'=1+1/(1+x^2)则y=f^2(u)dy/dx=2f(u)f'(u)u'=2f(u)f'(u)[1+1/(x+x^2)]

F(-∞,-∞)=A(B-π/2)(C-π/2)=0F(-∞,+∞)=A(B-π/2)(C+π/2)=0F(+∞,-∞)=A(B+π/2)(C-π/2)=0F(+∞,+∞)=A(B+π/2)(C+π/

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

y'=2xarctanx+1y''=2arctanx+2x/(1+x^2)y''/x=1=π/2+1

f(arctanx)d(arctanx)=F(arctanx)+cf(arctanx)[1/(1+x^2)]dx=F(arctanx)+c

dy/dx|x=0=df[(3x-2)/(3x+2)]/dx|x=0=arctan[(3x-2)/(3x+2)]^2*[(3x-2)/(3x+2)]'|x=0=3π/4

zx=1/(1+(x/y)²)*1/y=y/(x²+y²)zy=1/(1+(x/y)²)*(-x/y²)=-x/(x²+y²)所以

泰勒公式求arctanx（x）＝x-1/3*x^3+1/5*x^5-1/7*x^7+1/9*x^9...麦克劳林展开n阶导数是(-1)^(n-1)*1/(2n-1)*x^(2n-1)所以将t=n,t=

如图

f'(x)=2(arctanx)*1/(1+x^2)

不用推导,直接就是公式啊,=1/(1+x^2)

上下分别求导,arctanx求导=1/(1+x²）,分母求导为1,所以f(x)=arctanx/x的极限就等于1/(1+x²）的极限,当x趋于无穷大时1/(1+x²）趋于