作业帮 > 数学 > 作业

利用行列式的性质证明| 1 1 1 || t t^2 t^3 |=t^4(t-1)^3(t+1) [这里的数字都是次方)

来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/05/21 13:56:53
利用行列式的性质证明
| 1 1 1 |
| t t^2 t^3 |=t^4(t-1)^3(t+1) [这里的数字都是次方)
| t^2 t^4 t^6 |
证明:
| 1 1 1 |
| t t^2 t^3 |
| t^2 t^4 t^6 |
=1*t^2*t^6+1*t^3*t^2+1*t*t^4-1*t^2*t^2-1*t*t^6-1*t^3*t^4
=t^8+2t^5-t^4-2t^7
=t^4(t^4+2t-1-2t^3)
=t^4[(t^4-1)-2(t^3-t)]
=t^4[(t^2-1)(t^2+1)-2t(t^2-1)]
=t^4[(t^2-1)(t^2-2t+1)]
=t^4[(t-1)(t+1)(t-1)(t-1)]
=t^4(t-1)^3(t+1)
证毕.