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The function f(z) and g(z) are both analytic in the region |z|>10. These functions also satisfy |f(z)| < M and |g(z)| > E in this region, with M and E positive real numbers. What additional constraints are needed on the function g(z) in order to ensure \int f(z)/ g(z) dz =0 by using on;y integral bounds anf Cauchy's theorem? Assume these additional restrictions, show that this integral equals 0. Be sure to indicate where the additional assumptions are used in your proof. 原本覺得 這題需要g(z) 在 |z| > 10 沒有 root,這樣f/g就沒有pole, 那整個積分就可以把積分半徑取大一點 然後用Cauchy's inequality 證明是0? 想著想著又覺得怪怪的 說不清楚... -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 68.48.173.107