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The Integral Test Suppose f is a continuous, positive, decreasing function on [1, 00) and let an = f(n). Then the series _._, a, is convergent if and only if the improper integral , f(x) dx is convergent. In other words: (i) If ( f(x) dx is convergent, then _ an, is convergent. (ii) If [ f(x) dx is divergent, then _ a, is divergent.at to five 3. Estimate _" (2n + 1)- correct to five decimal places. This is 11.3 question so use the technique from that section. Show all work