幂级数∑（n=1→∞）(x-3)^n/n·3^n的收敛域是【 　 】．

级数前几项和s_n=a₁+a₂+…+a_n，若a_n≥0，判断数列｛s_n｝有界是级数a_n收敛的什么条件（）？

级数（lgx）ⁿ的收敛区域是：（）

下列程序段的执行结果为( )。 Dim A(3,3) For M=1 To 3 For N=1 To 3 If N=M Or N=3-M+1 Then A(M,N)=1 Else A(M,N)=0 End If Next N Next M For M=1 To 3 For N=1 To 3 Print A(M,N) Next N Print Next M

下列程序段的执行结果为 Dim A(3,3) For M=1 To 3 For N=1 To 3 If N=M Or N=3-M+1 Then A(M,N)=1 Else A(M,N)=0 End If Next N Next M For M=1 To 3 For N=1 To 3 Print A(M,N) Next N Print Next M

下列程序段的执行结果为( )。 Dim A(3，3) For M=1 To 3 For N=1 To 3 If N=M Or N=3-M+1 Then A(M, N)=1 Else A(M，N)=0 End If Next N Next M For M=1 To 3 For N=1 To 3 Print A(M，N) Next N Print Next M

In modern fathometers the sonic or ultrasonic sound waves are produced electrically by means of a(n)（）.

A declaration made by the Master before a PRC Consul，giving particulars regarding heavy weather or other incidents which may have caused damage to the vessel or cargo，through no fault of the vessel，her officers，or crew is a(n)（）.

A vessel or object being towed astern shall display a(n)（）.

已知级数的收敛域为［-1，3），则级数的收敛域为（）．

The movement of water away from the shore or downstream is called a(n)（）.

正项数值级数收敛，则达朗贝尔判别法是：当n趋于无穷时（）。