已知m平方加m减1等于0,求m的立方加2m的平方加2012.
问题描述:
已知m平方加m减1等于0,求m的立方加2m的平方加2012.
答
m³+2m²+2012
=(m³+m²)+m²+2012
=m(m²+m)+m²+2012
=m+m²+2012
=1+2012
=2013
答
m^3+2m^2+2012=m(m^2+m-1)+m^2+m-1+2013=2013
答
m²+m-1=0
则:
m²+m=1
又:
m³+2m²+2012
=(m³+m²)+m²+2012
=m(m²+m)+m²+2012
=m+m²+2012
=1+2012
=2013