Surface area problem in 3-d calculus

Click For Summary
SUMMARY

The discussion centers on calculating the surface area of the function z = (2/3)(x^(3/2) + y^(3/2)) over the domain 0 ≤ x ≤ 1, 0 ≤ y ≤ 1 using double integrals. The correct approach involves evaluating the double integral of the expression (1 + x + y)^(1/2) over the specified region. The final answer for the surface area is confirmed to be approximately 1.4066, achieved after correcting algebraic errors in the integration process.

PREREQUISITES
  • Understanding of double integrals in multivariable calculus
  • Familiarity with surface area calculations in 3D space
  • Knowledge of vector calculus, specifically cross products
  • Proficiency in algebraic manipulation and integration techniques
NEXT STEPS
  • Review the method for evaluating double integrals in multivariable calculus
  • Study the application of the cross product in vector calculus
  • Practice solving surface area problems using different functions
  • Explore numerical integration techniques for complex surfaces
USEFUL FOR

Students in calculus courses, particularly those studying multivariable calculus, as well as educators and tutors assisting with calculus homework and problem-solving strategies.

dukefanfromch
Messages
2
Reaction score
0

Homework Statement



Find the area of the surface.
The surface z = (2/3)(x^(3/2) + y^(3/2)), 0 </= x </= 1, 0 </= y </= 1

Homework Equations



Double integral over S of the magnitude of dr/du cross dr/dv dS, which equals the double integral over D of the magnitude of dr/du cross dr/dv dA.
(SSs |dz/dx X dz/dy|dS = SS D |dz/dx X dz/dy|dA)

The Attempt at a Solution


_ 1 1
I found the integral to be SS D (1+x+y)^(1/2) dA = SS (1+x+y)^(1/2) dxdy
_ 0 0
but my answer keeps coming out wrong. I might be making a mistake with algebra because I get a lot of different answers when i do it different ways. This is from an NC State Calculus 3 homework assignment, if anyone may have seen this problem before and remember how to do it. Help?
 
Last edited:
Physics news on Phys.org
dukefanfromch said:

Homework Statement



Find the area of the surface.
The surface z = (2/3)(x^(3/2) + y^(3/2)), 0 </= x </= 1, 0 </= y </= 1

Homework Equations



Double integral over S of the magnitude of dr/du cross dr/dv dS, which equals the double integral over D of the magnitude of dr/du cross dr/dv dA.
(SSs |dz/dx X dz/dy|dS = SS D |dz/dx X dz/dy|dA)

The Attempt at a Solution


_ 1 1
I found the integral to be SS D (1+x+y)^(1/2) dA = SS (1+x+y)^(1/2) dxdy
_ 0 0
but my answer keeps coming out wrong. I might be making a mistake with algebra because I get a lot of different answers when i do it different ways. This is from an NC State Calculus 3 homework assignment, if anyone may have seen this problem before and remember how to do it. Help?

What you have shown is completely correct. Now, how did you do that integration and what answer did you get?
 
I got the right answer finally, 1.4066. It was an algebraic error when I was evaluating the integral. Thanks for telling me I was doing it right though, that helped me know it wasn't a mistake in my set-up.
 

Similar threads

Replies
1
Views
2K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 3 ·
Replies
3
Views
5K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
11
Views
3K
  • · Replies 7 ·
Replies
7
Views
3K
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
4
Views
3K