Need some double integral help.

In summary, the conversation discusses the process of evaluating a double integral involving the function e^(y^3) with the given bounds for dy and dx. The individual is initially unsure of how to approach the problem, but is then given a tip on how to treat the "x" and "y" integrals separately. The conversation also mentions that the "y" integral may be more complicated, but it is eventually solved and the individual thanks the others for their help.
  • #1
ChargedTaco
6
0
Evaluate.

double integral (e^(y^3)) dy dx

Where dy is evaluated from sqrt(x/3) to 1

...and dx is evaluated from 0 to 3.

I am lost.
I don't even know how to start.:frown:
 
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  • #2
do u know how to do integrals?
double integral is just normal integrals in disguise, so when ou are doing the "y"-integral, you treat all "x"s in the integrand as just a constant, and while doing the "x"-integral you treat all "y"s as constant. Then, everything would then be exactly the same as a normal single integral. In many cases, whether you do the x or y integral first does not matter.
in your case i think you should do y first
 
  • #3
The "y" integration doesn't look pretty. It's basically

[tex] \int_{a}^{b} e^{y^3}{}dy [/tex]
 
  • #4
Hey guys yes I do know how to do integrals...however I don't know how to do this one. If I integrate y first I have to integrate e^(y^3)dy...and i don't know how to do this.

If I integrate x first then I'll end up with having to
integrate 3e^(y^3)dy...and I again I don't know how to do this.

Thanks.
 
  • #5
Here it is.

[tex]\int_{0}^{3} \int_{sqrt(x/3)}^{1} e^{y^3} {}dy} {}dx [/tex]

Yay! I got the latex code...however this is the only thing I know about this problem.
 
Last edited:
  • #6
Nevermind...I got it. Thanks guys.
 

Related to Need some double integral help.

1. What is a double integral?

A double integral is a mathematical concept that is used to calculate the area under a surface in two-dimensional space. It involves taking the limit of a sum of infinitely small rectangles to find the exact area.

2. When is a double integral used?

A double integral is used in many areas of science, such as physics, engineering, and statistics. It is commonly used to calculate the volume of a three-dimensional object or the mass of an object with varying density.

3. How do you solve a double integral?

To solve a double integral, you first need to determine the limits of integration for both variables. Then, you can use various techniques such as substitution, integration by parts, or partial fractions to simplify the integrand. Finally, you can integrate the resulting expression and evaluate it at the limits of integration.

4. What is the difference between a single and double integral?

A single integral is used to calculate the area under a curve in one-dimensional space, while a double integral is used to calculate the area under a surface in two-dimensional space. A double integral involves taking the limit of a sum of infinitely small rectangles, while a single integral involves taking the limit of a sum of infinitely small rectangles.

5. What are some real-world applications of double integrals?

Double integrals are used in many real-world applications, such as calculating the amount of fluid flowing through a pipe, determining the center of mass of an object, and finding the volume of irregularly shaped objects. They are also used in probability and statistics to calculate joint probabilities and expected values.

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