Question

求解两道vb程序设计题 求函数值

1、编程计算下列分段函数值：x由用户输入，按照“x=……，f(x)=……”的格式输出。
两道题目都一样 数据如图有两个 求解答 窗体设计也要

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Answer 1

Private Sub Command1_Click(Index As Integer)

DetermineFunctionalValue Index

End Sub

Private Sub DetermineFunctionalValue(ByVal i As Integer)

Print Command1(i).Caption + "：";

Dim x As Single, y As Single

x = InputBox("x=", "第(" & i + 1 & ")题", 0)

Select Case i

Case 0

y = Function_1(x)

Case 1

y = Function_2(x)

End Select

Print "x=" & x & "," & "f(x)=" & y

Print

End Sub

Private Function Function_1(ByVal x As Single) As Single

If x < 0 And x <> -3 Then

Function_1 = x ^ 2 + x - 6

ElseIf x >= 0 And x <> 2 And x <> 3 Then

Function_1 = x ^ 2 - 5 * x + 6

Else

Function_1 = x ^ 2 - x - 1

End If

End Function

Private Function Function_2(ByVal x As Single) As Single

If x < 1 And x <> -3 Then

Function_2 = 3 * x / 5

ElseIf x >= 1 And x < 10 Then

Function_2 = Abs(2 - 5 * x)

Else

Function_2 = Sqr(4 * x - 13)

End If

End Function

注:本程序窗体上的两个命令按钮是一个控件数组,其名称都是Command1,下标分别为0和1:

Command1(0),Command1(1);标题(Caption属性)分别为"第(1)题"和"第(2)题"。