解方程：(19x-x^2)/(x+1)*(x+(19-x)/(x+1))=84
问题描述：
解方程：(19x-x^2)/(x+1)*(x+(19-x)/(x+1))=84
答
(19x-x^2)/(x+1)*(x+(19-x)/(x+1))=84[(19x-x^2)/(x+1)]*[(x^2+19)/(x+1)]=8484(x+1)^2+(x^2+19)(x^2-19x)=0x^4-19x^2*(x-1)+84x^2-193x+84=0x^4-x^2*(19x-19)+(7x-12)(12x-7)=0(x^2-7x+12)(x^2-12x+7)=0(x-3)(x-4)(...