Question

1元3次方程求解x^3+3x^2+5x+8=0x^3+7x^2+14x+8=0x^3+6x^2+7x+9=0谁帮我解下这

Answer 1

设这3个式子分别为 A B C

令B-A 得4X^2+9X=0 解得 X=0或-9/4

令B-C 得X^2+7X-1=0 解得X=(-7+53^1/2)/2或(-7-53^1/2)/2

所以无解吧