若3X^2-X=1,求6X^3+7X^2-5X+2008的值_数学解答

若3X^2-X=1,求6X^3+7X^2-5X+2008的值

人气：287 ℃　时间：2019-12-07 15:17:27

解答

6X^3+7X^2-5X+2008
=2X(3X^2-X)+9X^2-5X+2008
=2X+9X^2-5X+2008
=3(3X^2-X)+2008
=3+2008
=2011