Question

关于VB6.0的一个程序设计

如何用VB6.0制作一个计算1元2次方程的程序？
ax^2+bx+c=0
在text 3个栏中输入a b c三个值
单击command1
在Lable栏中显示出X的值，且要考虑b^2-4ac

Answer 1

Private Sub Command1_Click()
Dim a As Single, b As Single, c As Single, R As Single
a = Val(Text1.Text): b = Val(Text2.Text): c = Val(Text3.Text)
R = b ^ 2 - (4 * a * c)
If R > 0 Then
MsgBox "有二个不相等的实根！"
X1 = (-b + Sqr(R)) / (2 * a)
X2 = (-b - Sqr(R)) / (2 * a)
ElseIf R = 0 Then
MsgBox "有二个相等的实根！"
X1 = (-b) / (2 * a)
X2 = (-b) / (2 * a)
ElseIf R < 0 Then
MsgBox "有二个不相等的虚根！"
X1 = CStr((-b) / (2 * a)) & "+" & CStr(Sqr(Abs(R)) / (2 * a)) & "i"
X2 = CStr((-b) / (2 * a)) & "-" & CStr(Sqr(Abs(R)) / (2 * a)) & "i"
End If
Label1.Caption = "x1=" & X1
Label2.Caption = "x2=" & X2
End Sub