Double Integral over General Region : Hass Section 13.2 - Problem 5

Click For Summary
SUMMARY

The discussion centers on solving a double integral problem from Hass Section 13.2, Problem 5, involving the function 3y³ * e^(xy) with outer integral limits from 0 to 1 and inner integral limits from 0 to y². The user struggles with the integration process, particularly with the inner integral, and questions the transition from 3y³ to 3y² as shown in the solutions manual. The correct approach involves recognizing the need for integration by parts to simplify the integration of the exponential function.

PREREQUISITES
  • Understanding of double integrals and their limits
  • Familiarity with integration by parts
  • Knowledge of exponential functions and their properties
  • Basic skills in evaluating definite integrals
NEXT STEPS
  • Study the method of integration by parts in detail
  • Practice evaluating double integrals with varying limits
  • Explore the properties of exponential functions in integration
  • Review examples of integrating products of polynomials and exponentials
USEFUL FOR

Students studying calculus, particularly those focusing on multivariable calculus and integration techniques, as well as educators looking for examples of double integrals and integration by parts.

atrain77abc
Messages
1
Reaction score
0

Homework Statement



Outer Integral: From zero to one dy
Inner Integral: from zero to y^2 dx

Function is: 3y^3 * e^(xy)


Homework Equations


None


The Attempt at a Solution



Have tried numerous u substitutions on e^(xy), but taking me nowhere. I am clearly doing something wrong. Assuming 3y^3 is a constant and does not need to be integrated when integrated with respect to x.

Solutions manual shows result of inner integral being [3y^2 * e^(xy)] from zero to y^2 - which appears to me that a y in the original 3y^3 simply disappeared! No idea how they are getting from 3y^3 to 3y^2 as the result of the first integration!

I am quite sure this is an easy problem and I am simply overlooking a very simple step.
 
Physics news on Phys.org
You need to use integration by parts.
 

Similar threads

Replies
5
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
Replies
24
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
10
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 27 ·
Replies
27
Views
3K
  • · Replies 17 ·
Replies
17
Views
4K
Replies
2
Views
1K