题目内容
命题“两直线平行,内错角相等”中,“两直线平行”是命题的________,“内错角相等”是命题的________.
下列代数式中:①3x+5y ②x2+2x+y2 ③0 ④-xy2 ⑤3x=0 ⑥单项式有________个,多项式有________个.
(1)5xy2-{2x2y-[3xy2-(xy2-2x2y)] ¸(xy)}
(2)(x-)(2x+1)(2x2+)(4x4+)(16x8+)¸(256x16-)
(3)