#calculus 2 power series bounds change

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reef mortar
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Hello. I just wanted to figure out why the lower bounds change when differentiating or integrating power series and is there a general rule to follow to know what that lower bound changes to?

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deft crown
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Show an example of what you mean

lone harbor
# reef mortar Hello. I just wanted to figure out why the lower bounds change when differentiat...

If you're talking about how, for instance, d/dx sum(n = 0, inf) x^n = sum(n = 1, inf) nx^(n - 1), you aren't necessarily "changing the bounds". Here's what's happening in full detail: d/dx sum(n = 0, inf) x^n = sum(n = 0, inf) d/dx x^n = sum(n = 0, inf) nx^(n - 1) = 0 * x^(-1) + sum(n = 1, inf) nx^(n - 1) = sum(n = 1, inf) nx^(n - 1)See, we didn't reindex, we just pulled out a term that equalled zero.