Question

m的平方加上2m减去2等于0，求m的三次方加上3m的平方再加上2014的值

Answer 1

m²+2m-2=0
m²+2m=2

所以m³+3m²+2014
=(m³+2m²)+m²+2014
=m(m²+2m)+m²+2014
=2m+m²+2014
=2+2014
=2016

Answer 2

∵m²+2m-2=0 ∴m²=2-2m 且m²+2m=2

m³+3m²+2014=m²(m+3)+2014
=(2-2m)(m+3)+2014
=-2m²-4m+6+2014
=-2m²-4m+2020
=-2(m²+2m)+2020
=-2x2+2020
=2016