假设2FB = AB得到 FB = √2/2FC = √(5/2)
作出G以后容易求出EF = √(5/2)EC = √5EC^2 = EF^2+FC^2所以EFC=90 与条件一致,所以2FB = AB的假设成立,即FB = √2/2,又 FC = √2FCB = arcsin(0.5)
假设2FB = AB得到 FB = √2/2FC = √(5/2)
作出G以后容易求出EF = √(5/2)EC = √5EC^2 = EF^2+FC^2所以EFC=90 与条件一致,所以2FB = AB的假设成立,即FB = √2/2,又 FC = √2FCB = arcsin(0.5)