已知代数式M²+M—1=0,那么代数式M³+2M²+2003等于?
问题描述:
已知代数式M²+M—1=0,那么代数式M³+2M²+2003等于?
答
M²+M—1=0
M²+M=1
M³+2M²+2003
=M﹙M²+M﹚+M²+2003
=M²+M+2003
=1+2003
=2004
答
M³+2M²+2003=(M²+M—1)*M+M²+M—1+2004=2004