Help With Calc 2 Problems: Integration & Differentiation

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The discussion focuses on two calculus problems involving integration and differentiation. The first problem is a definite integral that evaluates to zero, as the derivative of a constant is zero. The second problem involves integrating a function that is zero due to symmetry, which the participants emphasize is crucial for solving it. Substitution and integration by parts were attempted but did not yield results. The conversation highlights the importance of understanding the properties of integrals and derivatives in solving these calculus problems.
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Calc two help please :(

Ok, I have the following two problems:

\frac{d}{dx} \ \int_0^1 \ e^{tan^-1(t)} \ dt \\\\<br />

and

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

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.
 
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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.
 
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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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