若xm=2,xn=-,则xm+n的值为________________.
a2·a5= ________________.
-32×33= ________________.
x· ________________=-x7;(-a)4·(-a3)= ________________;-a2·(-a)2·(-a)3= ________________.
a2m+1=a2m·a(______)=am·a(______) .
计算:-y2·(-y)3·(-y)4=________________.