Diff EQ Intro - Verify Family of Functions as Solution

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SUMMARY

The discussion focuses on verifying a family of functions as a solution to the differential equation dy/dx + 2xy = 1, specifically y = e-x²∫(from 0 to x)edt + c1e-x². The key to solving this problem lies in applying the Fundamental Theorem of Calculus, which states that if F(x) = ∫ax f(t) dt, then F'(x) = f(x). By differentiating y with respect to x and substituting back into the differential equation, the terms simplify and confirm that the family of functions satisfies the equation.

PREREQUISITES
  • Understanding of differential equations, specifically first-order linear equations.
  • Familiarity with the Fundamental Theorem of Calculus.
  • Ability to differentiate functions involving integrals.
  • Knowledge of exponential functions and their properties.
NEXT STEPS
  • Study the Fundamental Theorem of Calculus in detail.
  • Practice solving first-order linear differential equations.
  • Learn techniques for differentiating integrals with variable limits.
  • Explore applications of exponential functions in differential equations.
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Students in introductory calculus or differential equations, educators teaching these concepts, and anyone looking to strengthen their understanding of solving differential equations using integral calculus.

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

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

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

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