For a holomorphic normal family, limits are holomorphic or identically infinity. A uniform bound at one interior point excludes infinity on its connected domain. Every sequence therefore has a finite locally uniform subsequential limit. The Cauchy integral formula makes the derivatives converge locally uniformly too, so the derivative family is normal. Without the point bound this can fail: tends uniformly to infinity on the unit disk, whereas its derivatives are not normal at zero.
Articles by others on the same topic
There are currently no matching articles.