Convergence tests. Game on.

Convergence tests is a grade 12 math skill: apply convergence tests (ratio, comparison, alternating series) to determine whether an infinite series converges. Below are 3 practice questions with answers and step-by-step explanations, drawn from the 5 convergence tests problems our math games drill.

5 questions in the bank
Kickoff

3 plays. No signup.

Warm-upeasy

The harmonic series 1n\displaystyle\sum \dfrac{1}{n} is:

The harmonic series is a p-series with p=1p = 1. Since p1p \le 1, it diverges.

Mid-gameeasy

Which test is best for n!nn\displaystyle\sum \dfrac{n!}{n^n}?

Factorials in the numerator make the Ratio test the natural choice.

Buzzer beatereasy

Which test should you try first for 1n2n\displaystyle\sum \dfrac{1}{n \cdot 2^n}?

The 2n2^n in the denominator makes the Ratio test efficient: an+1an12<1\dfrac{a_{n+1}}{a_n} \to \dfrac{1}{2} < 1.

Overtime

2 more. Played, not assigned.

The rest of the bank lives inside live head-to-head matches — the placement test finds the right starting difficulty.

Drill it inside a game.

The free placement test finds your level, then every match serves convergence tests questions at exactly the right difficulty.