Complex line integrals











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Suppose we have an analytic function then Why complex integral of that function does not depend on the path of integration?










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  • Read about Cauchy's theorem.
    – Richard Martin
    Nov 19 at 12:34










  • Because the integral around a closed loop is zero. This follows from Green's theorem in the plane. Look in any book on complex variables.
    – saulspatz
    Nov 19 at 12:35















up vote
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Suppose we have an analytic function then Why complex integral of that function does not depend on the path of integration?










share|cite|improve this question






















  • Read about Cauchy's theorem.
    – Richard Martin
    Nov 19 at 12:34










  • Because the integral around a closed loop is zero. This follows from Green's theorem in the plane. Look in any book on complex variables.
    – saulspatz
    Nov 19 at 12:35













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Suppose we have an analytic function then Why complex integral of that function does not depend on the path of integration?










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Suppose we have an analytic function then Why complex integral of that function does not depend on the path of integration?







complex-analysis contour-integration line-integrals analytic-functions






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asked Nov 19 at 12:31









robin

183




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  • Read about Cauchy's theorem.
    – Richard Martin
    Nov 19 at 12:34










  • Because the integral around a closed loop is zero. This follows from Green's theorem in the plane. Look in any book on complex variables.
    – saulspatz
    Nov 19 at 12:35


















  • Read about Cauchy's theorem.
    – Richard Martin
    Nov 19 at 12:34










  • Because the integral around a closed loop is zero. This follows from Green's theorem in the plane. Look in any book on complex variables.
    – saulspatz
    Nov 19 at 12:35
















Read about Cauchy's theorem.
– Richard Martin
Nov 19 at 12:34




Read about Cauchy's theorem.
– Richard Martin
Nov 19 at 12:34












Because the integral around a closed loop is zero. This follows from Green's theorem in the plane. Look in any book on complex variables.
– saulspatz
Nov 19 at 12:35




Because the integral around a closed loop is zero. This follows from Green's theorem in the plane. Look in any book on complex variables.
– saulspatz
Nov 19 at 12:35










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In general, the complex integral depends on the path of integration !



Example: $D= mathbb C setminus {0}, f(z)=1/z$ and $c(t)=e^{it}$ with $t in [0, 2m pi i]$ for some $m in mathbb N$.



Then we have $int_c f(z) dz = 2m pi i$.






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    In general, the complex integral depends on the path of integration !



    Example: $D= mathbb C setminus {0}, f(z)=1/z$ and $c(t)=e^{it}$ with $t in [0, 2m pi i]$ for some $m in mathbb N$.



    Then we have $int_c f(z) dz = 2m pi i$.






    share|cite|improve this answer

























      up vote
      1
      down vote













      In general, the complex integral depends on the path of integration !



      Example: $D= mathbb C setminus {0}, f(z)=1/z$ and $c(t)=e^{it}$ with $t in [0, 2m pi i]$ for some $m in mathbb N$.



      Then we have $int_c f(z) dz = 2m pi i$.






      share|cite|improve this answer























        up vote
        1
        down vote










        up vote
        1
        down vote









        In general, the complex integral depends on the path of integration !



        Example: $D= mathbb C setminus {0}, f(z)=1/z$ and $c(t)=e^{it}$ with $t in [0, 2m pi i]$ for some $m in mathbb N$.



        Then we have $int_c f(z) dz = 2m pi i$.






        share|cite|improve this answer












        In general, the complex integral depends on the path of integration !



        Example: $D= mathbb C setminus {0}, f(z)=1/z$ and $c(t)=e^{it}$ with $t in [0, 2m pi i]$ for some $m in mathbb N$.



        Then we have $int_c f(z) dz = 2m pi i$.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Nov 19 at 12:36









        Fred

        43.5k1644




        43.5k1644






























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