Is This Solution to the Integral and Series Problem Correct?

bengaltiger14
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Homework Statement


Evaluate the integral 3x^2e^xdx



The Attempt at a Solution



I used integration by parts twice and came up with:

3x^2e^x-6xe^x+6e^x+C

Does that look correct.


Another question ask for a divergent series whose terms go to 0.
The harmonic series 1/n (with infinity on top of summation and n=1 on bottom) fits that criteria correct?
 
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1. google the integrator and check
2. yes you are correct
 
Even more simply, differentiate (3x2- 6x+ 6)ex+ C and see what you get!
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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