Question

8．a,b,c为△ABC的三边3a3+6a2b-3a2c-6abc=O,

Answer 1

两边同时除以3abc

a^2/bc+2a/c-a/b-2=0

a/b(a/c-1)+2(a/c-1)=0

(a/b+2)(a/c-1)=0

因为a/b+2大于0

所以a/c-1=0

即a=c

所以三角形ABC是等腰三角形