钻石的密度、折射率、色散率分别是（） A: 3.52；2.417；0.044 B: 3.25；0.044；2.417 C: 3.52；2.147；0.044 D: 3.52；2.714；0.044

设[tex=2.071x1.286]HNND6HbpuBDrwNaIGlNy9w==[/tex]是数列，则下列命题正确的是 未知类型：{'options': ['若[tex=2.714x2.714]ySadpvq7BrEZCGdcnD6+ac1tTFR4ggf9GShRgT7R7oA=[/tex]收敛，则[tex=7.5x2.714]ySadpvq7BrEZCGdcnD6+aSgRSLAVpWqFyniHFvG4h4m5db8Vo3xylhwZBrnsbuzo[/tex]收敛', '若[tex=7.5x2.714]ySadpvq7BrEZCGdcnD6+aSgRSLAVpWqFyniHFvG4h4m5db8Vo3xylhwZBrnsbuzo[/tex]收敛，则[tex=2.714x2.714]ySadpvq7BrEZCGdcnD6+ac1tTFR4ggf9GShRgT7R7oA=[/tex]收敛', '若[tex=2.714x2.714]ySadpvq7BrEZCGdcnD6+ac1tTFR4ggf9GShRgT7R7oA=[/tex]收敛，则[tex=7.5x2.714]ySadpvq7BrEZCGdcnD6+aWz84Yv2ptg84GW0+u2nIHOxOgTbojkL2ctcb3S7eP0/[/tex]收敛', '若[tex=7.5x2.714]ySadpvq7BrEZCGdcnD6+aWz84Yv2ptg84GW0+u2nIHOxOgTbojkL2ctcb3S7eP0/[/tex]收敛，则[tex=2.714x2.714]ySadpvq7BrEZCGdcnD6+ac1tTFR4ggf9GShRgT7R7oA=[/tex]收敛'], 'type': 102}

判断下列级数的收敛性与绝对收敛性:[tex=2.714x2.714]ySadpvq7BrEZCGdcnD6+aTjAf9OTrKrECF976YooKuFreZLFJi7Zj2Rp9tZK79hn[/tex].

设级数[tex=2.714x2.714]ySadpvq7BrEZCGdcnD6+aevQSiUapl3qI6D/1lvgJVQ=[/tex]收敛，则必收敛的级数为 未知类型：{'options': ['[tex=5.286x2.714]ySadpvq7BrEZCGdcnD6+accVJN9KPzp1hjdpBe2PW5H1wwUmk7+OzNiL2Av08Ga3MNMzLZdxW2rPx8Xu0riSTg==[/tex]', '[tex=2.714x2.714]ySadpvq7BrEZCGdcnD6+acmJvIfh2uCX8dO8NRr4G3EgRGUHA/Qc7jf0ksOcNO+D[/tex]', '[tex=7.5x2.714]ySadpvq7BrEZCGdcnD6+acpCuist9iyX+/cOGxFe02z0HwrmPXVeKCxW98OAPoe5FK+JT8YnrYnjDo0gD2qY5Q==[/tex]', '[tex=6.714x2.714]ySadpvq7BrEZCGdcnD6+aUSs8NjqGM34Pj0L/aWjPf66+/w82GQur4sqKPd1Z3pbUhADuGmasFe+dg7T+191TQ==[/tex]'], 'type': 102}

下述各项正确的是 未知类型：{'options': ['若[tex=2.714x2.714]ySadpvq7BrEZCGdcnD6+acmJvIfh2uCX8dO8NRr4G3EgRGUHA/Qc7jf0ksOcNO+D[/tex]和[tex=2.571x2.714]ySadpvq7BrEZCGdcnD6+ab2J/4llOznj+QTaPdxN/9qKAvvceo8i5QCsz6jMGKQ1[/tex]都收敛，则[tex=6.071x2.714]ySadpvq7BrEZCGdcnD6+aUSs8NjqGM34Pj0L/aWjPf7NEQlygK/GBk8INvZkVCWgHhJ1+6t3xXSQ0vWtb3LkdA==[/tex]收敛', '若[tex=4.214x2.714]ySadpvq7BrEZCGdcnD6+aZ5wBaTmYs3kpllncenRLNg6EFuCnKNSPI1hBgjqrZahdcqEZ0dOFsqHNWuvzez+Fw==[/tex]收敛，则[tex=2.714x2.714]ySadpvq7BrEZCGdcnD6+acmJvIfh2uCX8dO8NRr4G3EgRGUHA/Qc7jf0ksOcNO+D[/tex]与[tex=2.571x2.714]ySadpvq7BrEZCGdcnD6+ab2J/4llOznj+QTaPdxN/9qKAvvceo8i5QCsz6jMGKQ1[/tex]都收敛', '若正项级数[tex=2.714x2.714]MQZm3AhDTnJFsv42JLsPgdr6mjVJ8Utu8wopfHhPw/s=[/tex]发散，则[tex=3.143x2.0]1KwVH0BHYCJDtxf+Cy5OxM6szsUF/d9obSlHeROSA8PvQMG7k7E+S8hulCG0kVzc[/tex]', '若级数[tex=2.714x2.714]ySadpvq7BrEZCGdcnD6+aevQSiUapl3qI6D/1lvgJVQ=[/tex]收敛，且[tex=3.357x1.286]1KwVH0BHYCJDtxf+Cy5OxJTBKaOUVHQ9Mnw0r3elcBM=[/tex][tex=5.571x1.286]yrxqbq9Fo5LoBPgFKOwWKVEYoDBNNA4etAJlzTPGMkU=[/tex]，则级数[tex=2.571x2.714]ySadpvq7BrEZCGdcnD6+aayyu4AmWOU4Pubzp4EThMk=[/tex]也收敛'], 'type': 102}

下列变量组（）是一个闭回路。 A: {x，x，x，x，x，x} B: {x，x，x，x，x} C: {x，x，x，x，x，x} D: {x，x，x，x，x，x}

以下谓词蕴含式正确的是（）: (∀x) (A(x)→B(x))=>( ∀x)A(x)→(∀x)B(x)|(∀x) (A(x)↔B(x))=>( ∀x)A(x)↔(∀x)B(x)|(∀x)A(x)∨(∀x)B(x)=>( ∀x) (A(x)∨B(x))|(∃x) (A(x)∧B(x))=>(∃x)A(x)∧(∃x)B(x)

以下谓词蕴含式正确的是（）: (?x) (A(x)→B(x))=>( ?x)A(x)→(?x)B(x)|(?x) (A(x)?B(x))=>( ?x)A(x)?(?x)B(x)|(?x)A(x)∨(?x)B(x)=>( ?x) (A(x)∨B(x))|(?x) (A(x)∧B(x))=>(?x)A(x)∧(?x)B(x)

若级数[tex=2.714x2.714]ySadpvq7BrEZCGdcnD6+aevQSiUapl3qI6D/1lvgJVQ=[/tex]收敛，则下列级数中收敛的是[input=type:blank,size:6][/input] . 未知类型：{'options': ['[tex=6.071x2.714]ySadpvq7BrEZCGdcnD6+aUSs8NjqGM34Pj0L/aWjPf772dbvk2QiSp7dpZ7/MAB/[/tex]', '[tex=6.071x2.714]ySadpvq7BrEZCGdcnD6+aUSs8NjqGM34Pj0L/aWjPf5gD082w4ii+e+OqGCOiJxW[/tex]', '[tex=4.143x2.714]ySadpvq7BrEZCGdcnD6+aU4qHJeokQihJ889W6SoMTMNic2Q0WF4HG183yVB6bRm[/tex]', '[tex=6.143x2.714]ySadpvq7BrEZCGdcnD6+aSBPXJbZEuHno1IyUm3MXawCF8vRFcwHVVo/h7fl237cWbwsu4EidIs3G9PvuqJk8A==[/tex]'], 'type': 102}

下列式中错误的是： A: (∀x)(A(x)Úp(x)) Û (∀x)A(x)Ú (∀x)p(x) B: ($x)A(x) Ù p Û ($x)(A(x) Ù p ) C: (∀x)(A(x)ÚB(x)) Þ (∀x)A(x)Ú( ∀x)B(x) D: ($x)(A(x)ÙB(x)) Þ ($x)A(x)Ù( $x)B(x)