x3+2xy-x-xy2.
原式=x(x2+2y-1-y2)
=x[x2-(y2-2y+1)]
=x(x+y-1)(x-y+1).
带征
下列哪一种情况可形成T1加权像()
A.长TR,短TE
B.长TR,长TE
C.短TR,短TE
D.长TE
E.短TE