你可能感兴趣的试题
2x+y-3=0 x+y-1=0 x-y-3=0 2x-y-5=0
a>ab>ab2 ab2>ab>a ab>a>ab2 ab>ab2>a
2x-y-5=0 2x+y-3=0 x+y-1=0 x-y-3=0
若ab=0,则a=0 若a≠0,则ab≠0 若ab=0,则a≠0 若ab≠0,则a≠0
x-y-3=0 2x+y-3=0 x+y-1=0 2x-y-5=0
x﹣y﹣3=0 2x+y﹣3=0 x+y﹣1=0 2x﹣y﹣5=0
a>ab>ab2 ab2>ab>a ab>a>ab2 ab>ab2>a
x-y-3=0 2x+y-3=0 x+y-1=0 2x-y-5=0
若A2=0,则A=0. 若A2=A,则A=E或A=0. 若AX=AY,且A≠0,则X= Y. 若AB=0,则A,B不一定是零矩阵.
若AB∥DC,则∠1=∠2 若AD∥BC,则∠3=∠4 若∠1=∠2,则AB∥DC 若∠2+∠3+∠A.=180°,则AB∥DC
若命题p:∃x∈R.,x2﹣x+1=0,则¬p:∀x∈R.,x2﹣x+1≠0 “sinθ=”是“θ=30°”的充分不必要条件 命题“若a=0,则ab=0”的否命题是:“若a≠0,则ab≠0” 已知p:∃x∈R.,cosx=1,q:∀x∈R.,x2﹣x+1>0,则“p∧¬q”为假命题
若a>b,则ac2>bc2 若>,则a>b 若a3>b3且ab<0,则> 若a2>b2且ab>0,则<