如果x²—3x+1=0,求x3+1÷x3

2025-01-04 07:32:26
推荐回答(1个)
回答1:

x3-3x+1=0------x-3+1/x=0 x+1/x=3
x3+1/x3=(x+1/x)(x2-1+1/x2)=3*((x+1/x)2-3)=3*(9-3)=18