Question

已知3x的三次方-x=1,求9x的四次方+12x的三次方-7x+2009=?

Answer 1

3x^3-x=1
x^3=（1+X）/3
将x^3=（搜亩1+X）/3代入搜漏颂世郑9x^4+12X^3-7x+2009得
=3x^2+2013

Answer 2

3x^3-x=1 x=7/高汪渗8—戚脊—陵埋8/9
9x^4+12X^3-7x+2009=(9x^4-3x^2)+(12x^3-4x)+3x^2-3x+2009
=3x+4+3x^2-3x+2009=3x^2+2013=x+2014