(X^2+mx+n)(x^2-3x+2)=x^4+(m-3)x³+(2+n-3m)x²+(2m-3n)x+2n ∵不含有x^3项和x项∴m-3=0 2m-3n=0∴m=3 n=2
(X^2+mx+n)(x^2-3x+2)-3+M=0,M=32M-3N=0N=2
