Derivative Problem: I'm Unsure of My Work

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Homework Help Overview

The discussion revolves around the differentiation of a function involving an integral, specifically the expression y=e^{-x^{2}} ∫^{x}_{0} e^{t^{2}} dt + c_{1}e^{-x^{2}}. Participants are examining the application of the product rule in this context and questioning the treatment of the integral as a constant.

Discussion Character

  • Conceptual clarification, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the application of the product rule to the differentiation of the function, with some questioning whether the integral should be treated as a constant. There is also a concern about the presence of the variable "t" in the integral affecting the differentiation process.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the integral's role in the differentiation process. Some guidance has been offered regarding the validity of the product rule, but there is no explicit consensus on the correctness of the original poster's approach.

Contextual Notes

Participants note that the problem is related to verifying a solution to the differential equation y'+2xy=1, which adds complexity to the discussion regarding the integral's treatment.

Lancelot59
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I'm unsure of my work when completing this problem:

[tex]y=e^{-x^{2}} \int^{x}_{0} e^{t^{2}} dt + c_{1}e^{-x^{2}}[/tex]

I applied the product rule to the left bit.

[tex]\frac{dy}{dx}=e^{-x^{2}} e^{x^{2}} + e^{-x^{2}}(-2x)\int^{x}_{0} e^{t^{2}} dt + (-2x)c_{1}e^{-x^{2}}[/tex]

I'm fairly certain I did this wrong.
 
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I believe that:
[tex]\int^{x}_{0} e^{t^{2}} dt[/tex]
Is a constant with respect to x, so you don't need to use the product rule, just treat it like any other constant
 
JHamm said:
I believe that:
[tex]\int^{x}_{0} e^{t^{2}} dt[/tex]
Is a constant with respect to x, so you don't need to use the product rule, just treat it like any other constant

No, this is a function with respect to x, so the product rule is valid here.
 
So I derived it correctly?
 
I'm certain you did it right. Why do you think otherwise?

RGV
 
Ray Vickson said:
I'm certain you did it right. Why do you think otherwise?

RGV

It's from a problem where I need to verify that it is a solution to:

[tex]y'+2xy=1[/tex]

I was concerned that the integral still containing the "t" variable wouldn't cancel, however upon re-inspection I think it should.
 

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