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Checko
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Homework Statement
Let Sumation "a sub n" be an absolutely convergent series, and "b sub n" a bounded sequence. Prove that sumation "a sub n"*"b sub n" is convergent. (sorry fist time on this site and can't use the notation.)
Homework Equations
Theorem A: that states sumation "a sub n" = A and sumation "b sub n" = B. Then
1. Sumation ("a sub n" + "b sub n") = A + B
2. For each k in Real, sumation (k*"a sub n") = k sumation "a sub n" if when k does not = 0
Theorem B: if sumation "a sub n" converges absolutely then sumation "a sub n" converges
The Attempt at a Solution
Since "b sum n" is bounded there exist a real number M that is the bound. I then use M as a constant and bring it out of the sumation so that we have "M * sumation "a sub n""
We are now left with the the original absolutly convergent series times M. I know M must be greater than or = to 0 by definition of bounded. So the series will converge at ever point except 0. 0 can not be used .
Please give some direction to my maddness. Thanks