x(x+2)(x+6)+20x+6=0
问题描述：
x(x+2)(x+6)+20x+6=0
答
x(1)=(38361^(1/2)/9 + 559/27)^(1/3) - 32/(9*(38361^(1/2)/9 + 559/27)^(1/3)) - 8/3,
x(2)=16/(9*(38361^(1/2)/9 + 559/27)^(1/3)) - (38361^(1/2)/9 + 559/27)^(1/3)/2 - 8/3- 3^(1/2)*i*(16/(9*(38361^(1/2)/9 + 559/27)^(1/3)) + (38361^(1/2)/9 + 559/27)^(1/3)/2)*i ,
x(3)=16/(9*(38361^(1/2)/9 + 559/27)^(1/3)) - (38361^(1/2)/9 + 559/27)^(1/3)/2 - 8/3+ 3^(1/2)*(16/(9*(38361^(1/2)/9 + 559/27)^(1/3)) + (38361^(1/2)/9 + 559/27)^(1/3)/2)*i ,
化简一下就是
x(1)=-0.196959489589038;
x(2)=-3.90152025520548 - 3.90400522823014 i;
x(3)=-3.90152025520548+3.90400522823014 i
答案很复杂.自己验算一下哦.