解决一下数学题分解因式1.1/2p^2-2pq2.-3x+6x^2-3x^33.a^2（a-3)-a+34.2xy-x^

1。1/2p^2-2pq=p(p/2-2q)2。-3x+6x^2-3x^3=-3x(x^2+2x+1)=-3x(x+1)^23。a^2（a-3)-a+3=a^2(a-3)-(a-3)=(a^2-1)(a-3)=(a+1)(a-1)(a-3)4。2xy-x^2-y^2+1=-(x^2-2xy+y^2)+1=1-(x-y)^2=(1-x+y)(1+x-y)