求用VB编写一元一次方程

比如x=logx+5

Private Sub Command1_Click()
Dim x As Single, x1 As Single, x2 As Single
Do
x1 = Val(InputBox("下限(>0)", , 0.000001))
Y1 = f(x1)
Loop Until x1 > 0
Do
x2 = Val(InputBox("上限(>下限)", , 0.001))
Y2 = f(x2)
Loop Until x2 > x1
If Sgn(Y1) = Sgn(Y2) Then
MsgBox "给定范围内无解"
Exit Sub
End If
Do
x = x1 - Y1 * (x2 - x1) / (Y2 - Y1)
y = f(x)
If Abs(y) < 0.0000000001 Then Exit Do
If Sgn(y) = Sgn(Y1) Then
x1 = x
Y1 = y
Else
x2 = x
Y2 = y
End If
Loop Until x2 - x1 < 0.00001
Print "其解为：" & x
End Sub

Private Function f(x As Single) As Single
f = x - Log(x) / Log(10) - 5
End Function

带过程？

带过程的就很麻烦了。要用到大量公式，也许要用数据库。

只要结果就是普通的运算嘛。

我现在手头没VB ，又很久没用了，不太确定怎么用。

但思路就是 赋值运算啊。