Line integral on triangle with given vertices

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Let $F$ be a vector field such that $$vecF=langle x^2,y^2,zrangle$$ Integration over the line segments which form the triangle with vertices $(0,0,0)$,$(0,2,0)$,$(0,0,2)$ can be achieved by parametrizing each segment and then evaluating $$sum_i=1^3int_C_ivecF(r_i^(x)(t),r_i^(y)(t),r_i^(z)(t))cdot vecr^prime_i(t),dt$$ with $vecr_i(t)$ being the parametrization of the $i$-th segment $C_i$.



However, taking into account that $F$ is a vector field with potential function $$f(x,y,z)=frac2x^3+2y^3-3z^26$$ and thus conservative, according to the generalised fundumental theorem of line integrals, since all the components $F_1(x,y,z),F_2(x,y,z),F_3(x,y,z)$ of $vecF$ are continuous in $mathbbR^3$, it follows that $$oint_CvecF,dvecr=fbig(r^(x)(0),r^(y)(0),r^(z)(0)big)-fbig(r^(x)(0),r^(y)(0),r^(z)(0)big)=0$$ given that $r(t)$ is a parametrization of $C$ (the whole triangle), which is a closed loop (same starting and endpoint). Is this true?







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    Let $F$ be a vector field such that $$vecF=langle x^2,y^2,zrangle$$ Integration over the line segments which form the triangle with vertices $(0,0,0)$,$(0,2,0)$,$(0,0,2)$ can be achieved by parametrizing each segment and then evaluating $$sum_i=1^3int_C_ivecF(r_i^(x)(t),r_i^(y)(t),r_i^(z)(t))cdot vecr^prime_i(t),dt$$ with $vecr_i(t)$ being the parametrization of the $i$-th segment $C_i$.



    However, taking into account that $F$ is a vector field with potential function $$f(x,y,z)=frac2x^3+2y^3-3z^26$$ and thus conservative, according to the generalised fundumental theorem of line integrals, since all the components $F_1(x,y,z),F_2(x,y,z),F_3(x,y,z)$ of $vecF$ are continuous in $mathbbR^3$, it follows that $$oint_CvecF,dvecr=fbig(r^(x)(0),r^(y)(0),r^(z)(0)big)-fbig(r^(x)(0),r^(y)(0),r^(z)(0)big)=0$$ given that $r(t)$ is a parametrization of $C$ (the whole triangle), which is a closed loop (same starting and endpoint). Is this true?







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      Let $F$ be a vector field such that $$vecF=langle x^2,y^2,zrangle$$ Integration over the line segments which form the triangle with vertices $(0,0,0)$,$(0,2,0)$,$(0,0,2)$ can be achieved by parametrizing each segment and then evaluating $$sum_i=1^3int_C_ivecF(r_i^(x)(t),r_i^(y)(t),r_i^(z)(t))cdot vecr^prime_i(t),dt$$ with $vecr_i(t)$ being the parametrization of the $i$-th segment $C_i$.



      However, taking into account that $F$ is a vector field with potential function $$f(x,y,z)=frac2x^3+2y^3-3z^26$$ and thus conservative, according to the generalised fundumental theorem of line integrals, since all the components $F_1(x,y,z),F_2(x,y,z),F_3(x,y,z)$ of $vecF$ are continuous in $mathbbR^3$, it follows that $$oint_CvecF,dvecr=fbig(r^(x)(0),r^(y)(0),r^(z)(0)big)-fbig(r^(x)(0),r^(y)(0),r^(z)(0)big)=0$$ given that $r(t)$ is a parametrization of $C$ (the whole triangle), which is a closed loop (same starting and endpoint). Is this true?







      share|cite|improve this question











      Let $F$ be a vector field such that $$vecF=langle x^2,y^2,zrangle$$ Integration over the line segments which form the triangle with vertices $(0,0,0)$,$(0,2,0)$,$(0,0,2)$ can be achieved by parametrizing each segment and then evaluating $$sum_i=1^3int_C_ivecF(r_i^(x)(t),r_i^(y)(t),r_i^(z)(t))cdot vecr^prime_i(t),dt$$ with $vecr_i(t)$ being the parametrization of the $i$-th segment $C_i$.



      However, taking into account that $F$ is a vector field with potential function $$f(x,y,z)=frac2x^3+2y^3-3z^26$$ and thus conservative, according to the generalised fundumental theorem of line integrals, since all the components $F_1(x,y,z),F_2(x,y,z),F_3(x,y,z)$ of $vecF$ are continuous in $mathbbR^3$, it follows that $$oint_CvecF,dvecr=fbig(r^(x)(0),r^(y)(0),r^(z)(0)big)-fbig(r^(x)(0),r^(y)(0),r^(z)(0)big)=0$$ given that $r(t)$ is a parametrization of $C$ (the whole triangle), which is a closed loop (same starting and endpoint). Is this true?









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      asked Aug 3 at 21:00









      Andrewtz98

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          Yep, this is good, as there are no singularities in the potential function.






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            You have the correct conclusion, but didn’t really need to compute a scalar potential to reach it. $vec F$ is defined on all of $mathbb R^3$ and a simple calculation confirms that it is irrotational, so you can conclude that it is conservative.






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              2 Answers
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              active

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              2 Answers
              2






              active

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              active

              oldest

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              active

              oldest

              votes








              up vote
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              down vote



              accepted










              Yep, this is good, as there are no singularities in the potential function.






              share|cite|improve this answer

























                up vote
                1
                down vote



                accepted










                Yep, this is good, as there are no singularities in the potential function.






                share|cite|improve this answer























                  up vote
                  1
                  down vote



                  accepted







                  up vote
                  1
                  down vote



                  accepted






                  Yep, this is good, as there are no singularities in the potential function.






                  share|cite|improve this answer













                  Yep, this is good, as there are no singularities in the potential function.







                  share|cite|improve this answer













                  share|cite|improve this answer



                  share|cite|improve this answer











                  answered Aug 3 at 21:18









                  Isaac Browne

                  3,7112928




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                      You have the correct conclusion, but didn’t really need to compute a scalar potential to reach it. $vec F$ is defined on all of $mathbb R^3$ and a simple calculation confirms that it is irrotational, so you can conclude that it is conservative.






                      share|cite|improve this answer

























                        up vote
                        1
                        down vote













                        You have the correct conclusion, but didn’t really need to compute a scalar potential to reach it. $vec F$ is defined on all of $mathbb R^3$ and a simple calculation confirms that it is irrotational, so you can conclude that it is conservative.






                        share|cite|improve this answer























                          up vote
                          1
                          down vote










                          up vote
                          1
                          down vote









                          You have the correct conclusion, but didn’t really need to compute a scalar potential to reach it. $vec F$ is defined on all of $mathbb R^3$ and a simple calculation confirms that it is irrotational, so you can conclude that it is conservative.






                          share|cite|improve this answer













                          You have the correct conclusion, but didn’t really need to compute a scalar potential to reach it. $vec F$ is defined on all of $mathbb R^3$ and a simple calculation confirms that it is irrotational, so you can conclude that it is conservative.







                          share|cite|improve this answer













                          share|cite|improve this answer



                          share|cite|improve this answer











                          answered Aug 3 at 23:28









                          amd

                          25.6k2943




                          25.6k2943






















                               

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