f(x)=(1+x)+ (1+x)2+ (1+x)3+ …+ (1+x)n展开式中x2项的系数为Tn,求Tn再求Tn/(n3+2n)的极限，n趋向正无穷！麻烦说下过程

f(x)={2x+1,x f(x)={1+x/2,x f(x)=(x-1)/(x+2) f(x)+f((x-1)/x)=2x; x!=0,1; 求f(x) f(x)+f[(x-1)/x]=2x x不等于0,1.求f(x). max{f(x),g(x)}=1/2(f(x)+g(x)+|f(x)-g(x)| f(x)满足:2f(x)-f(1/x)=x+1,求f(x) 若f(x)满足f(x)-2f(1/x)=x,则f(x)=? 若F(x)满足f(x)+2f(1/x)=x,则f(x)= 设函数f(x)满足f(x)+2f(1/x)=x,求f(x) 已知f(x)满足2f(x)+f(1/x)=3x,求f(x) F(X)满足F(x)+2f(x分之1)=3X,求f(x) 已知f(x)满足2f(x)+f(1/x)=3x,求f(x)? 已知f(x)满足2f(x)+f(-x)=-3x+1,求f(x) 已知f(x)满足f(x)+2f(1/x)=3x,求f(x) , 已知f(x+1/x)=x^2+1/x^2+1/x则f(x) 设2f(x)+xf(1/x)=(x+2x)/(x+1),求f(x). 函数F(x)=2x,x>=1,F(x)=x^2,x