Tubular Integration by Parts

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Tabular Method Suppose  and  . Then if we set up a table, differentiating f(x) as many times as it takes to get to zero and integrating g(x) as many times, we get
DI
 (a)
 (b)+  (a)
 (c)-  (b)
+  (c)
Notice how we alternate the signs in the “I” column. Then, multiplying rows with like letters (which you can skip on your own paper to help make this clearer - draw arrows instead from (a) to (a), etc.) gives the following directly as the anti-derivative: This method is much faster than the f-g method or the older u-v, especially for iterated (more than once) integrals by parts