Is [0,∞] e^(-x^3) dx an Improper Integral?

Jbreezy
Messages
582
Reaction score
0

Homework Statement


It just wants me to tell whether this is improper or not.
[0,infinity] e^(-x^3) dx

Homework Equations




I say Yes

The Attempt at a Solution

 
Physics news on Phys.org
I don't see why it would be improper. What's your reasoning?
 
I'm not 100 percent sure. I said yes because I think it keeps going it's domain is all real.
 
Jbreezy said:

Homework Statement


It just wants me to tell whether this is improper or not.
[0,infinity] e^(-x^3) dx

Homework Equations




I say Yes

The Attempt at a Solution


What definition of "improper integral" are you using?
 
Jbreezy said:

Homework Statement


It just wants me to tell whether this is improper or not.
[0,infinity] e^(-x^3) dx

Homework Equations




I say Yes

The Attempt at a Solution

I would call this integral --
$$\int_0^{\infty}e^{-x^3}dx$$
-- improper, because of the upper limit of integration.
 
I'm just using the def in stewart calc. I think it is improper thanks.
 
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...
Back
Top