设\( A \)为\( n \) 阶方阵, \( B \)是\( A \)经过若干次初等变换后得到的矩阵,则( ) A: \( \left| A \right| = \left| B \right| \) B: \( \left| A \right| \ne \left| B \right| \) C: 若\( \left| A \right| = 0 \) ,则必有 \( \left| B \right| = 0 \) D: 若\( \left| A \right| > 0 \),则一定有\( \left| B \right| > 0 \)
设\( A \)为\( n \) 阶方阵, \( B \)是\( A \)经过若干次初等变换后得到的矩阵,则( ) A: \( \left| A \right| = \left| B \right| \) B: \( \left| A \right| \ne \left| B \right| \) C: 若\( \left| A \right| = 0 \) ,则必有 \( \left| B \right| = 0 \) D: 若\( \left| A \right| > 0 \),则一定有\( \left| B \right| > 0 \)
方程\( \ln x = ax \)\( \left( {a > 0} \right) \)只有一个实根( )
方程\( \ln x = ax \)\( \left( {a > 0} \right) \)只有一个实根( )
设`\A`是`\m \times n`矩阵,`\m` 小于 `\n`,则必有 ( ) A: \[\left| {{A^T}A} \right| \ne 0\] B: \[\left| {{A^T}A} \right| = 0\] C: \[\left| {A{A^T}} \right| > 0\] D: \[\left| {A{A^T}} \right| < 0\]
设`\A`是`\m \times n`矩阵,`\m` 小于 `\n`,则必有 ( ) A: \[\left| {{A^T}A} \right| \ne 0\] B: \[\left| {{A^T}A} \right| = 0\] C: \[\left| {A{A^T}} \right| > 0\] D: \[\left| {A{A^T}} \right| < 0\]
下列选项中可以将表格的某一行文本的对齐方式设置为向下对齐的是( )。 A: <tdvalign=”right”> B: <tdvalign=”foot”> C: <tralign=”bottom”> D: <trvalign=”bottom”>
下列选项中可以将表格的某一行文本的对齐方式设置为向下对齐的是( )。 A: <tdvalign=”right”> B: <tdvalign=”foot”> C: <tralign=”bottom”> D: <trvalign=”bottom”>
若幂级数\(\sum\limits_{n = 1}^\infty { { a_n}} {x^n}\)在\(x = {x_0}\)处发散,则该级数的收敛半径满足( )。 A: \(R = \left| { { x_0}} \right|\) B: \(R < \left| { { x_0}} \right|\) C: \(R > \left| { { x_0}} \right|\) D: \(R \le \left| { { x_0}} \right|\)
若幂级数\(\sum\limits_{n = 1}^\infty { { a_n}} {x^n}\)在\(x = {x_0}\)处发散,则该级数的收敛半径满足( )。 A: \(R = \left| { { x_0}} \right|\) B: \(R < \left| { { x_0}} \right|\) C: \(R > \left| { { x_0}} \right|\) D: \(R \le \left| { { x_0}} \right|\)
实二次型\( f = {X^T}AX\left( { { A^T} = A} \right) \)为正定的充分必要条件是( ) A: \( R\left( A \right) = n \) B: \(A\)的负惯性指数为零 C: \( \left| A \right| > 0 \) D: \(A\)的特征值全大于零
实二次型\( f = {X^T}AX\left( { { A^T} = A} \right) \)为正定的充分必要条件是( ) A: \( R\left( A \right) = n \) B: \(A\)的负惯性指数为零 C: \( \left| A \right| > 0 \) D: \(A\)的特征值全大于零
下面表达式的值为真的是______。 A: Mid("Visual Basic",1,12)=Right("Programming Language Visual Basic",12) B: "ABCRG">"abcde" C: Int(134.69)>=Cint(134.69) D: 78.9/32.77<=97.5/43.97 And –45.4>-4.98
下面表达式的值为真的是______。 A: Mid("Visual Basic",1,12)=Right("Programming Language Visual Basic",12) B: "ABCRG">"abcde" C: Int(134.69)>=Cint(134.69) D: 78.9/32.77<=97.5/43.97 And –45.4>-4.98
Before administering a medication, the nurse must verify the rights of medication administration, which include: A: right patient, right bed, right drug, right route, right dose, and right time. B: right drug, right dose, right route, right time, right physician, and right documentation. C: right patient, right drug, right route, right time, right documentation, and right equipment. D: right patient, right drug, right dose, right concentration, right route, right time, and expiration date.
Before administering a medication, the nurse must verify the rights of medication administration, which include: A: right patient, right bed, right drug, right route, right dose, and right time. B: right drug, right dose, right route, right time, right physician, and right documentation. C: right patient, right drug, right route, right time, right documentation, and right equipment. D: right patient, right drug, right dose, right concentration, right route, right time, and expiration date.
表示水平线对齐方式为左对齐的HTML代码是()。 A: <bralign=left> B: <tralign=left> C: <hralign=left> D: <hralign=right>
表示水平线对齐方式为左对齐的HTML代码是()。 A: <bralign=left> B: <tralign=left> C: <hralign=left> D: <hralign=right>
比较化合物乙酸(Ⅰ)、乙醇(Ⅱ)、苯酚(Ⅲ)、碳酸(Ⅳ)的酸性大小( ) A: Ⅰ>Ⅲ>Ⅱ>Ⅳ B: Ⅰ>Ⅳ>Ⅲ>Ⅱ C: Ⅰ>Ⅱ>Ⅳ>Ⅲ D: Ⅰ>Ⅲ>Ⅳ>Ⅱ
比较化合物乙酸(Ⅰ)、乙醇(Ⅱ)、苯酚(Ⅲ)、碳酸(Ⅳ)的酸性大小( ) A: Ⅰ>Ⅲ>Ⅱ>Ⅳ B: Ⅰ>Ⅳ>Ⅲ>Ⅱ C: Ⅰ>Ⅱ>Ⅳ>Ⅲ D: Ⅰ>Ⅲ>Ⅳ>Ⅱ