Derivative Problem: I'm Unsure of My Work

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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.