Help With Calc 2 Problems: Integration & Differentiation

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Homework Help Overview

The discussion revolves around two calculus problems involving integration and differentiation, specifically focusing on a definite integral and an indefinite integral. The subject area is calculus, particularly the concepts of integration and differentiation.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • The original poster attempts substitution and integration by parts for both problems but expresses difficulty in making progress. Some participants question the validity of the first integral's form and its evaluation, while others highlight the implications of symmetry in the second integral.

Discussion Status

The discussion is ongoing, with participants providing insights and questioning assumptions about the integrals. There is a suggestion that the first integral is a constant, leading to a derivative of zero, while the second integral's evaluation is influenced by its symmetry. No consensus has been reached, but various interpretations are being explored.

Contextual Notes

The original poster mentions a change in the limits of the first integral, which may affect the evaluation. There is also a concern about the nature of the functions involved and their solvability in terms of elementary functions.

mewmew
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Calc two help please :(

Ok, I have the following two problems:

[tex]\frac{d}{dx} \ \int_0^1 \ e^{tan^-1(t)} \ dt \\\\[/tex]

and

[tex] \int \ \frac{Sin[x]}{1+x^2} \ dx<br /> [/tex]

I have tried to do substitution on both and integration by parts on the second one but nothing seems to work. If I could just get some pointers in the right direction on where to start that would be awesome, thanks a lot.
 
Last edited:
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1.Are you sure about the first...?In the form posted,it's zero...
2.It's not an integral solvable in the "family" of "elementary"functions.

Daniel.
 
1. I am not sure why its 0, but that is the form the problem is in and 0 is what I got when I did it in Mathematica. I am not really sure on how to go about evaluating it though as if I do U substitution I get x in my denominator.

2.If it makes any difference it is actually an definite integral with lower limit -1 and upper limit 1. I don't think that should make a difference however.

Thanks for the help.
 
Last edited:
mewmew said:
1. I am not sure why its 0, but that is the form the problem is in. I am not really sure on how to go about evaluating it though as if I do U substitution I get x in my denominator.

2.If it makes any difference it is actually an definite integral with lower limit -1 and upper limit 1. I don't think that should make a difference however.

Thanks for the help.


OMG,for #2,it MAKES A HUGE DIFFERENCE...The integral is zero for symmetry reasons...

1.the first integral,in the form u posted is a number.The derivative of a number wrt any variable (x,y,z,t,...) is IDENTICALLY ZERO.

Daniel.
 
Thanks a lot!
 

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