You've an exam on series what essential things are there to know integral ratio test root test maclaurin Taylor pseries etc Can someone explain?

Answer 1

Let us call a series S, it is hard to put all the notation we need here, because we do not have the proper characters, but I will try. 1. One type of series is a geometries series. It converges if for the sum q^n where n goes from 0 to inginitye, q is stritclty between -1 and 1. 2. Consider an integer N and a non-negative monotone decreasing function f defined on the unbounded interval l [N, ∞). Then the series converges if and only if the integral is finite. If the integral diverges so does the series. 3. Assume that for all n, an> 0. Suppose that there exists r such that the limit as n goes to infinity of |a_n+1/a_n)|=r If r < 1, then the series converges. If r > 1, then the series diverges. If r = 1, the ratio test is inconclusive, and the series may converge or diverge. 4. The root test looks at the limsup of the nth root of |a_n|=r, as n goes to infinity. If r<1 the series converges if r>1 it diverges and if r=1 the test tells us nothing