Computing antiderivatives (integration)

Nitrate
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Homework Statement


integrate 4e^(2x)^(1/2) - 1/7e^(-pix)
using a guess and check method (haven't learned many rules of integration)


Homework Equations





The Attempt at a Solution


i'm not really sure how to do this integral... i tried
4/(2x)^(1/2)[e^(2x)^(1/2)] using a table of antiderivatives for the first part
but when i differentiated it, it did not give me the original function
i haven't tried the second bit yet.
 
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For the second term, do you know how to differentiate exponential functions?

Can you answer these questions, differentiate with respect to x:

e^x
18e^x
4e^2x
e^(x^2)
e^(x^(1/3))
e^(8x^(-2/3))

For the first term you need to use a substitution, try substituting u=x^1/2
 
If you have \int f'(x)e^{f(x)}dx you could make the substitution u= f(x) so that du= f'(x)dx and the integral becomes \int e^u du= e^u+ C= e^{f(x)}+ C

HOWEVER, if that f'(x) is not in the integral originally (and is not a constant), you cannot put it in! Here, I don't believe that \int e^{(4x)^{1/2}}dx can be integrated in terms of elementary functions.
 
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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