Question

若三个数a,b,c满足a+b+c=0,abc=1,则a的立方+b的立方+c的立方等于多少?

Answer 1

韦达形等幂和

a^3+b^3+c^3

=(a+b+c)^3-3(a+b+c)(ab+ac+bc)+3abc=3