14/11/18 02:09:23.09
>>82
x^3+ax^2+bx+c=(x-k)(x-m)(x-n)=x^3-(k+m+n)x^2+(km+kn+mn)x-kmn
a=-(k+m+n), b=km+kn+mn, c=-kmn
a^2+bc=0 より (k+m+n)^2=kmn(km+kn+mn)
all 0 しかねーだろ?
14/11/18 02:09:23.09
>>82
x^3+ax^2+bx+c=(x-k)(x-m)(x-n)=x^3-(k+m+n)x^2+(km+kn+mn)x-kmn
a=-(k+m+n), b=km+kn+mn, c=-kmn
a^2+bc=0 より (k+m+n)^2=kmn(km+kn+mn)
all 0 しかねーだろ?