在△ABC中,a^3+b^3+c^3/a+b+c=c^2,sinAsinB=3/4
问题描述：
在△ABC中,a^3+b^3+c^3/a+b+c=c^2,sinAsinB=3/4
求三角形的形状
答
(a^3+b^3+c^3)/(a+b+c)=c^2a^3+b^3+c^3=ac^2+bc^2+c^3a^3+b^3-ac^2-bc^2=0(a+b)(a^2-ab+b^2)-c^2(a+b)=0(a+b)(a^2-ab+b^2-c^2)=0a+b≠0a^2-ab+b^2-c^2=0c^2=a^2+b^2-2abcosC2abcosC=abcosC=1/2C=60°A+B=120°sinAsi...