級數和

請使用For........ Next迴圈計算下列級數前20項之和
加入一個Label元件，將答案顯示在裡面。

                    級數形式                                     數學式

[參考解答]

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim s, n, i, b
　

---

第1題

s = 0
For n = 1 To 20
  

s = '寫出數學式
　

Next
Label1.Text = s
　

---

第2題

s = 0
For n = 1 To 20
 

s = '寫出數學式

Next n
Label1.Text = s
　

---

第3題

s = 1
For n = 1 To 19

s =  '寫出數學式
　

Next
Label1.Text = s
　

---

第4題

s = 1
For n = 1 To 19

s = '寫出數學式
　

Next
Label1.Text = s
　

---

第5題

s = 0
For n = 1 To 20
  b = 1
    For i = 1 To 2 * (n - 1)      '計算n!
       b *=  i
    Next i

s= '寫出數學式
　

Next
Label1.Text = s
End Sub