vb 一元二次方程的复根问题

下面是我写的，只是考虑 b*b -4ac>0时的实根，如何把复根也放进来，谢谢了，希望能详细给我说一下...
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<br>Dim a As Integer, b As Integer, c As Integer
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<br>rivate Sub Command1_Click()
<br>If a &lt;&gt; 0 And (b * b) - 4 * a * c &gt;= 0 Then
<br>Text4.Text = Val((-b + Sqr((b * b) - 4 * a * c)) / 2 * a)
<br>Text5.Text = Val((-b - Sqr((b * b) - 4 * a * c)) / 2 * a)
<br>Else
<br>i = MsgBox("b*b-4ac&lt;0 无法计算", 0 + 64, "方程无实根")
<br>End If
<br>End Sub
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<br>rivate Sub Text1_Click()
<br>strs1 = "请输入a的值" + Chr(13) + Chr(10) + "然后单击确定"
<br>a = InputBox$(strs1, "输入框", , 100, 100)
<br>Text1 = a
<br>If Text1 = 0 Then
<br>i = MsgBox("a不能为零", 5 + 48, "重新输入a的值")
<br>End If
<br>End Sub
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<br>rivate Sub Text2_Click()
<br>strs2 = "请输入b的值" + Chr(13) + Chr(10) + "然后单击确定"
<br>b = InputBox$(strs2, "输入框", , 100, 100)
<br>Text2 = b
<br>End Sub
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<br>Private Sub Text3_Click()
<br>strs3 = "请输入c的值" + Chr(13) + Chr(10) + "然后单击确定"
<br>c = InputBox$(strs3, "输入框", , 100, 100)
<br>Text3 = c
<br>End Sub

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