用简便方法计算(2010的3次方+2010的2次方-2011)分之(2010的3次方-2×2010的2次方-2008)
展开全部
解:设A=2010
∴原式=(2010^3+2010^2-2011)/(2010^3-2*2010^2-2008)
=(A^3+A^2-A-1)/(A^3-2A^2-A+2)
=(A+1)(A^2-1)/[A^3-A^2-(A^2+A-2)]
=(A+1)^2(A-1)/[A^2(A-1)-(A-1)(A+2)]
=(A+1)^2(A-1)/(A-1)(A^2-A-2)
=(A+1)^2(A-1)/(A-1)(A-2)(A+1)
=(A+1)/(A-2)
=(2010+1)/(2010-2)
=2011/2008
遇到较大或较复杂的数或式子最好用换元的思想
望采纳
∴原式=(2010^3+2010^2-2011)/(2010^3-2*2010^2-2008)
=(A^3+A^2-A-1)/(A^3-2A^2-A+2)
=(A+1)(A^2-1)/[A^3-A^2-(A^2+A-2)]
=(A+1)^2(A-1)/[A^2(A-1)-(A-1)(A+2)]
=(A+1)^2(A-1)/(A-1)(A^2-A-2)
=(A+1)^2(A-1)/(A-1)(A-2)(A+1)
=(A+1)/(A-2)
=(2010+1)/(2010-2)
=2011/2008
遇到较大或较复杂的数或式子最好用换元的思想
望采纳
推荐律师服务:
若未解决您的问题,请您详细描述您的问题,通过百度律临进行免费专业咨询