也试一个几何解

来源: 于 2024-02-06 20:00:34 [旧帖] [给我悄悄话] 本文已被阅读：次

Draw diameter AD. Because angle ABC is 45 degrees, so is angle D. Meanwhile, Angle ACD=90 degrees. 
AC = sqrt(16+1)=sqrt(17). Then AD = sqrt(2)*AC= sqrt (34).