I just took my Calculus II final and I have a question about this

flyingpig
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Homework Statement





I spoke to a few people and pretty much everyone but me seem to know what is going on with a few questions. This question was one of the ones I stared blankly for a few minutes and then wrote down an answer

\int_{0}^{2} e^{x^2} d\theta



The Attempt at a Solution



Look, it is with respect to theta, no x (not that you can even integrate it if it is x...)

I read some MVC on my own so I didn't have "too much" trouble with it, but I just wondered why it was put on a Calc II exam...

I asked the professor if it was a typo (twice) and he shooked his head saying "nope".

So solving you should get 2e^{x^2}

Now my question is, (well I have more than one...)

1. Am I right?
2. If not, what single variable calculus techniques do you use to find the solution?
 
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flyingpig said:

Homework Statement





I spoke to a few people and pretty much everyone but me seem to know what is going on with a few questions. This question was one of the ones I stared blankly for a few minutes and then wrote down an answer

\int_{0}^{2} e^{x^2} d\theta



The Attempt at a Solution



Look, it is with respect to theta, no x (not that you can even integrate it if it is x...)

I read some MVC on my own so I didn't have "too much" trouble with it, but I just wondered why it was put on a Calc II exam...

I asked the professor if it was a typo (twice) and he shooked his head saying "nope".

So solving you should get 2e^{x^2}

Now my question is, (well I have more than one...)

1. Am I right?
2. If not, what single variable calculus techniques do you use to find the solution?

1. Yes.
 
Good, lol. Why the hell did my professor put up this kind of question on the exam anyways?
 
To see if you were paying attention to details such as the variable of integration, θ. Apparently you were paying attention.
 
Even if you weren't paying attention how could you integrate e^(x^2)? Also, how could a Cal II student know to treat e^(x^2) as a constant and not a variable?
 
flyingpig said:
Even if you weren't paying attention how could you integrate e^(x^2)? Also, how could a Cal II student know to treat e^(x^2) as a constant and not a variable?
Because it's a non-elementary integral and thus they should rub their eyes and take a second look at the question? It's well known result that ex2 and e-x2 cannot be evaluated analytically. This is a matter of paying attention to what you're doing rather than plugging and chugging(even if it's a cookbook course). We know that the dependent variable is whatever we're integrating with respect to, and everything else(not containing the dependent variable) can be held constant.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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