计算:xy2·(-x2)=_________.
计算:(-2xy)(3x2y-2x+1)=_________.
在x+p与x2-2x+1的积中不含x,则p的值为_________.
计算:-3xy2z·(x2y)2=_________.
计算:-3a(4b-1)=_________.
要使(x2+ax+1)(-6x3)的展开式中不含x4项,则a应等于( )
A. 6 B. -1 C. D. 0