题目
下列级数中绝对收敛的是()A. sum_(n=1)^infty (-1)^n (1)/(n)B. sum_(n=2)^infty (-1)^n+1 (1)/(ln n)C. sum_(n=1)^infty (-1)^n+1 (1)/(nsqrt(n))D. sum_(n=2)^infty (-1)^n+1 (1)/(nln n)
下列级数中绝对收敛的是()
A. $\sum_{n=1}^{\infty} (-1)^n \frac{1}{n}$
B. $\sum_{n=2}^{\infty} (-1)^{n+1} \frac{1}{\ln n}$
C. $\sum_{n=1}^{\infty} (-1)^{n+1} \frac{1}{n\sqrt{n}}$
D. $\sum_{n=2}^{\infty} (-1)^{n+1} \frac{1}{n\ln n}$
题目解答
答案
C. $\sum_{n=1}^{\infty} (-1)^{n+1} \frac{1}{n\sqrt{n}}$