已知,a是方程x²-3x+1=0的根求2 a³×a²-5a²×a²+2a³-8a²/a²+1

问题描述:

已知,a是方程x²-3x+1=0的根求2 a³×a²-5a²×a²+2a³-8a²/a²+1

a2-3a=-1
a2=3a-1
2a5-5a4+2a3-8a2/a2+1=
-2a3+a4+2a3-8a2/a2+1
=a4-8a2/a2+1
=3a3-a2-8a2/a2+1
=3a3-9a2/a2+1
=9a2-3a-9a2/3a-1+1
=-3a/3a=-1