1/a²+1/b²=1/h²??? 设AB=c；SRT△ABC=AC*BC/2=AB*CD/2b*a=c*hab=cha²+b²=c² 1/a²+1/b²=b²/(ab)²+a²/(ab)²=(a²+b²)/(ab)²=c²/(ch)²=1/h²
