lim_(n→∞)(({2^n)+(3^n)})/(({2^n+1)+{3^n+1)}}= ____ .$\lim_{n→∞}\frac{{{2^n}+{3^n
2.lim_(n to infty)(sqrt(n+1)-sqrt(n))sqrt(n+1)=_____.2.$\lim_{n \to \infty}(\sqr
幂级数sum_(n=0)^infty((-1)^n)/(n+1)z^n+1在|z|A. ln(1+z)B. ln(1-z)C. ln$\frac{1}{1+z}
+dfrac ({x)_(n+1)}({x)_(n)})
[判断题] 数列{xn}=(-1)n /(n+1)存在极限。A . 正确B . 错误
9.(2025·全国一卷·高考真题)设数列(a_{n)}满足a_(1)=3,(a_(n+1))/(n)=(a_(n))/(n+1)+(1)/(n(n+1))(1
求幂级数 sum _(n=1)^infty n(n+1)(x)^n 的收敛域及和函数并求 sum _(n=1)^infty dfrac (n(n+1))({2)
18 单选 lim_(n to infty) ((n)/(n+1))^n=( ).A. eB. 1C. 1/eD. ∞
【例43】lim_(ntoinfty)((1)/(n+1)+(1)/(n+2)+...+(1)/(n+n))=____【例43】$\lim_{n\to\inft
已知数列(an)的通项公式为 _(n)=dfrac ({(-1))^n+1}(n), 则 _(5)= __ ,_(8)= __ 1