M*N+P=( x�0�5+5x-a)( -x+2)+( x3+3x�0�5+5)=[-x3+(2-5)x�0�5+(a+10)x-2a] +( x3+3x�0�5+5)=(a+10)x-2a+5∵M*N+P的值与x的取值无关∴(a+10)x=0a=-10
M*N+P=-x^3-5x�0�5+ax+2x�0�5+10x-2a+x^3+3x�0�5+5=(a+10)x-2a+5与x无关，则a+10=0,a=-10
