Let be a series with positive terms and suppose
Then
2. If or , the series diverges.
3. If , the series may converge or diverge.
The test is also called the Cauchy ratio test or d'Alembert ratio test.
Let be a series with positive terms and suppose
Then
2. If or , the series diverges.
3. If , the series may converge or diverge.
The test is also called the Cauchy ratio test or d'Alembert ratio test.
Weisstein, Eric W. "Ratio Test." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/RatioTest.html