计算极限:[tex=7.357x2.714]MqOfsQLAB/zeVSdv1WggGCBEsZPtaboI/n/4A1Zo00ZvQ0S0l463OXfH3CdJDCtEBwjh3bJeGX8pSteFf9PSnttkbzaGYLmY6s2Een+eQso=[/tex].

用换元积分法求不定积分：[tex=7.357x2.714]7q2q65BbYYeA+0NVY5kbGw4nuvXsi0csecRFt4qVo5TaaTNf70m5x7u6oiWLBYDjBrslNetlP5PoycluOi4sA3C0iAvXWc4iE/OT94dzmbQ=[/tex]。

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

求下列函数的累次极限[tex=6.0x1.929]Wh0BbcsxbdPTUak0FdVk/R/RgRsbJzr4R6onyz3Qj+hvMMGiNJUnFjiwZij8Teki4igdC7Pux+TfobQYvgAmuQ==[/tex]及[tex=6.0x1.929]4pg/bo8Hx9EQO+9S5vF7XmC5gy7BwA/SagQVsJKpH7fpzc9y5dWm/t3Yke0vZeVhT+Rapp8ueZd+lWhDuepXCQ==[/tex]：[tex=7.357x2.714]uiDmly95rjcfniG+94Y4QPQr16riNnS9YPZiNJMza6e6kSs94Vzeeu1TneiJJU2r[/tex].

设向量组[tex=5.857x1.0]7pNelk4HUVBg38zOC/iSU88HyqryjOXVFLrLi0G37BtCjaM1P4n64NP/bp1YR5EC[/tex], 线性无关，向量 [tex=7.357x2.714]B7BX9/J9INzI95jSH8w/G95Qi+t6/W8jVS5n4LHL5xYzwxmZpzMxRIOapG8r76l+afWKOF38CAaYvzeOE53qHQ==[/tex].证明: 向量组[tex=10.143x1.143]79UdqJgb1GktTDberHD7uFMef7iUtpCtQWY2pVGZ05wO0jXYCdroXc84b41/RiYlxNoKk3jFAs/rWX3usx2TAFG+vTDT6X6ONTMmHvZBGQIqRkQ2S8Bl6kOFh0y7y0DkQRckke9hlFXvQLP00UqD+INWDNE1yoA++jWzJbvQpRc=[/tex]线性无关.

下列级数中绝对收敛的是[input=type:blank,size:6][/input] . 未知类型：{'options': ['[tex=5.357x2.714]ySadpvq7BrEZCGdcnD6+aTA5YZwdRnDTPnojmB3KZN1UTVgz+HVuqd4pTif7FugV6pCXniQ+/pAiaylXY0KZqg==[/tex]', '[tex=6.786x2.714]ySadpvq7BrEZCGdcnD6+aSm/7rCnRZEEi5ZomxortdsWJMsLTlMPyKJTs5WOlh/lAiYSz87pikVNQHaUAS4zeQ==[/tex]', '[tex=4.357x2.714]ySadpvq7BrEZCGdcnD6+aTA5YZwdRnDTPnojmB3KZN2llPrlAOhKC5KVnZipLi4q5qbZvjX6/gogg8FO6nBWQQ==[/tex]', '[tex=7.357x2.714]ySadpvq7BrEZCGdcnD6+aTA5YZwdRnDTPnojmB3KZN227rVMEsYWAyUPQzVZ/IqZSVWB/R2sdbAzOiL6MmZHPA==[/tex]'], '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)

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)