Line integral on triangle with given vertices

The name of the pictureThe name of the pictureThe name of the pictureClash Royale CLAN TAG#URR8PPP











up vote
0
down vote

favorite












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























    up vote
    0
    down vote

    favorite












    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





















      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      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?









      share|cite|improve this question










      share|cite|improve this question




      share|cite|improve this question









      asked Aug 3 at 21:00









      Andrewtz98

      1397




      1397




















          2 Answers
          2






          active

          oldest

          votes

















          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













            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





















              Your Answer




              StackExchange.ifUsing("editor", function ()
              return StackExchange.using("mathjaxEditing", function ()
              StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
              StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
              );
              );
              , "mathjax-editing");

              StackExchange.ready(function()
              var channelOptions =
              tags: "".split(" "),
              id: "69"
              ;
              initTagRenderer("".split(" "), "".split(" "), channelOptions);

              StackExchange.using("externalEditor", function()
              // Have to fire editor after snippets, if snippets enabled
              if (StackExchange.settings.snippets.snippetsEnabled)
              StackExchange.using("snippets", function()
              createEditor();
              );

              else
              createEditor();

              );

              function createEditor()
              StackExchange.prepareEditor(
              heartbeatType: 'answer',
              convertImagesToLinks: true,
              noModals: false,
              showLowRepImageUploadWarning: true,
              reputationToPostImages: 10,
              bindNavPrevention: true,
              postfix: "",
              noCode: true, onDemand: true,
              discardSelector: ".discard-answer"
              ,immediatelyShowMarkdownHelp:true
              );



              );








               

              draft saved


              draft discarded


















              StackExchange.ready(
              function ()
              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2871490%2fline-integral-on-triangle-with-given-vertices%23new-answer', 'question_page');

              );

              Post as a guest






























              2 Answers
              2






              active

              oldest

              votes








              2 Answers
              2






              active

              oldest

              votes









              active

              oldest

              votes






              active

              oldest

              votes








              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










                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




                  3,7112928




















                      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













                        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






















                               

                              draft saved


                              draft discarded


























                               


                              draft saved


                              draft discarded














                              StackExchange.ready(
                              function ()
                              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2871490%2fline-integral-on-triangle-with-given-vertices%23new-answer', 'question_page');

                              );

                              Post as a guest













































































                              Comments

                              Popular posts from this blog

                              Color the edges and diagonals of a regular polygon

                              Relationship between determinant of matrix and determinant of adjoint?

                              What is the equation of a 3D cone with generalised tilt?