[[곡선,curve]] 폐곡선 closed curve's orientation: ||positive ||ccw || ||negative ||cw || 단어 contour 윤곽, 등고선 path_integral이라고 안하네. TBW: Compare: 단어만 보면 [[선적분,line_integral]]과 비슷한데 둘의 차이를 구분해서 서술. 같은거? Def. Let $f$ be defined at points of a smooth curve $C$ defined by $x=x(t),\,y=y(t),\;a\le t\le b.$ The '''contour integral''' of $f$ along $C$ is: $\int_C f(z)dz=\lim_{||P||\to0}\sum_{k=1}^{n} f(z_k^*) \Delta z_k$ (Zill AEM Def 18.1.1) Thm. Evaluation of a Contour Integral If $f$ is continuous on a smooth curve $C$ given by $z(t)=x(t)+iy(t),\;a\le t\le b,$ then: $\int_C f(z)dz=\int_a^b f(z(t))z'(t)dt$ (Zill AEM Thm 18.1.1) = 성질 properties = 다음은 익숙 * ∫,,C,, kf(z)dz= k∫,,C,, f(z)dz * ∫,,C,, (f(z) + g(z))dz = ∫,,C,, f(z)dz + ∫,,C,, g(z)dz * ∫,,C,, f(z)dz = ∫,,C₁,, f(z)dz + ∫,,C₂,, f(z)dz 여기서 C는 매끄러운 곡선 C₁, C₂의 union 다음을 기억 $\int_{-C}f(z)dz=-\int_C f(z)dz$ 여기서 -C는 반대 방향(orientation)을 의미(denote). = thm = [[코시-구르사_정리,Cauchy-Goursat_theorem]] [[유수정리,residue_theorem]] ---- [[https://terms.naver.com/entry.naver?docId=5668872&ref=y&cid=60207&categoryId=60207 수학백과: 경로적분법]] [[WpKo:경로적분법]] Up: [[적분,integration]] [[복소해석,complex_analysis]]