x4+x2-2.
x4+x2-2,
=(x2+2)(x2-1),
=(x2+2)(x+1)(x-1).
It's cold. you'd better _____ more clothes.[ ]
A. put on
B. wear
C. to put on
国际长途电话号码的字冠是()。
A、00
B、0
C、1
D、8