已知M=x+3y-3z,N=-2x+5y-z且M+N+P=0.求多项式P
问题描述:
已知M=x+3y-3z,N=-2x+5y-z且M+N+P=0.求多项式P
答
M+N=x+3y-3z-2x+5y-z=-x+8y-4z
M+N+P=0,P=-(M+N)
P=-(-x+8y-4z)=x-8y+4z