Need help in finding Limits of Integration (Calc 3)

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SUMMARY

The discussion focuses on evaluating the integral of the dot product of two vectors, f and n, over the surface defined by the equation x + y + z = 1 in Calculus 3. The vector f is defined as (x², e^y, 1), while the normal vector n is determined to have a magnitude of 1 and a direction normal to the surface. The integration limits for x and y are established as 0 to infinity, with z constrained by the equation z = 1 - x - y. The surface element dS is expressed as dS = c dx dy.

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  • Understanding of vector calculus and surface integrals
  • Familiarity with dot products and vector notation
  • Knowledge of the equation of a plane in three-dimensional space
  • Basic concepts of limits of integration in multiple integrals
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  • Learn how to express normal vectors for different surfaces
  • Explore the application of the Divergence Theorem in surface integrals
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Students and educators in calculus, particularly those studying vector calculus and surface integrals, as well as anyone seeking to deepen their understanding of integration limits in three dimensions.

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Need help in finding Limits of Integration! :) (Calc 3)

Homework Statement



Evaluate


Integral: f * n dS, where "f" and "n" are vectors and "*" is DOT PRODUCT.

Where,

where
(a) f = (x2, ey, 1),

S: x + y + z = 1, x ≥ 0, y ≥ 0, z ≥

Homework Equations



ummm none

The Attempt at a Solution



So, I figured that:
r(u,v) = (u,v,1-u-v)
f (x(u),y(v)) = u2, ev, 1)

I also got N vector, which is 1.

BUT HOW DO I FIND THE INTEGRATION LIMITS?!

I know that "x ≥ 0, y ≥ 0, z ≥ ", but how does this help me? Are the integration limits from
0 to INFINITY?

PLease Help! I have been trying to think for 48 hours on this!

THanks!
 
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The normal isn't 1, it's a vector, so it'll have compenents, what is the vector. You're integrating over a surface S, what is this surface?
 


The integration limits are for x and y from 0 to infinite and for z equal to 1-x-y. Since f doesn't depend on z this doesn't matter.

n is the vector with magnitude 1 and direction normal to the surface x+y+z=1.

Find a way to express n in (a,b,c) notation and the element of surface dS as a function of dx and dy. Then f*n=ax^2+be^y+c.

dS will be dS=cdxdy.
 
Last edited:

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