已知钝角三角形ABC的三边长分别为a,a+1,a+2(a∈N+),则a=

问题描述:

已知钝角三角形ABC的三边长分别为a,a+1,a+2(a∈N+),则a=

则a²+(a+1)²a²+a²+2a+1a²a²-2a-3(a+1)(a-3)-1a1=0
a2=1
a3=2
a1=0与a2=1均不符合题意,所以
a=2a²+(a+1)²