问题 填空题 化简:2a2b24a3b=______;x2-1y•y2x+1=______. 答案 2a2b24a3b=b2a,x2-1y•y2x+1=(x+1)(x-1)y•y2x+1=y(x-1)=xy-y,故答案为:b2a,xy-y.