已知:A=-x2-1,A-B=-x^3+2x^2-5,求B

问题描述:

已知:A=-x2-1,A-B=-x^3+2x^2-5,求B

A=-x2-1,A-B=-x^3+2x^2-5
B=A-(-x^3+2x^2-5)=-x2-1+x^3-2x^2+5=x^3-3x^2+4