Diff EQ Intro - Verify Family of Functions as Solution

jgiarrusso
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Homework Statement


Verify that the indicated family of functions is a solution of the given differential equation. Assume an appropriate interval I of definition for each solution.


Homework Equations


dy/dx + 2xy = 1; y = e-x2\int(from 0 to x)et2dt + c1e-x2


The Attempt at a Solution


I have only had one class period in differential so far and we didn't get to go over much material. I imagine that one would need to differentiate y(x) with respect to x and plug into the first equation. However, I'm not quite sure what to do with the integral with respect to t. I tried to integrate it, and got et2/(2t), but evaluating that at 0 would cause an implosion. If I differentiate with respect to x, I don't think I can just treat it as a constant because it's evaluated from 0 to x. Could I please get a nudge in the right direction?
 
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I'm not quite sure what to do with the integral with respect to t.

This is just simple application of Fundamental Theorem of Calculus.

If F(x) = \int_a^x f(t) dt then F'(x) = f(x), given of course that f(x) is continuous on [a, x].
 
So then dy/dx would be:

dy/dx = e-x2 * ex2 - 2xe-x2\int(from 0 to x)et2dt - 2xc1e-x2

And then plugging it into the differential equation, it all cancels out. Thank you so much!
 
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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