Ratio and Root Tests

Ratio Test

  1. $\rhd$ Ratio test (8:58) Introduction to the ratio test. Does the series $\displaystyle\sum_{n=5}^{\infty}\dfrac{n^{10}}{n!}$ converge or diverge?
  2. * Practice Ratio test. (4 problems)

Root Test

  1. $\rhd$ Root test (10:07) Introduction to the root test.
    • Does the series $\displaystyle\sum_{n=1}^{\infty}\left(\dfrac{n^{2}+1}{2n^2+1}\right)^n$ converge or diverge?
    • Does the series $\displaystyle\sum_{n=1}^{\infty}\left(\dfrac{n^n}{3^{1+3n}}\right)^{1/n}$ converge or diverge?
    • Does the series $\displaystyle\sum_{n=1}^{\infty}\left(\dfrac{n}{n+1}\right)^{n^2}$ converge or diverge?