若三角形的三边长分别为2,5-x,x-1,则x的取值范围是___ __.
( _________ )(3a﹣2b)=12a2b﹣8ab2.
若A是单项式,且A(4x2y3+3xy2)=﹣12x3y5﹣9x2y4,则A2= _________ .
= ;= .
计算:(﹣2xy2)2•3x2y•(﹣x3y4)= .
3y2•(﹣y)3= .