from n=1 to infinity of ((-1)^n * n)/3^n does it converge or diverge, and what is the sum? good luck!!!
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It's convergent by the alternating series test. while .
Last edited by disclaimer; Apr 24th 2008 at 10:14 AM.
Hello, alex_nicole! We have: . . . . Multiply by Add:. . . . . . . . . The series has the sum: . And we have: . Therefore: .
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