用vb编写一个程序求一元二次方程ax2+bc+c=0的根

Question

急！

Answer 1

用^表示幂,当b^2－4ac≥0时的根为．x=(-b±√(b^2-4ac))/(2a)称为一元二次方程的求根公式当b^2－4ac>0时,有两个不同的根当b^2－4ac=0时,有两个相同的根当b^2－4ac<0时,没有实数根.Private Sub Command1_Click()
Dim a, b, c
a = CDbl(InputBox("输入a值:"))
b = CDbl(InputBox("输入b值:"))
c = CDbl(InputBox("输入c值:"))
If b ^ 2 - 4 * a * c < 0 Then
Print "没有实根"
Else
Print "X1=" & (-b + Sqr(b ^ 2 - 4 * a * c)) / (2 * a)
Print "X2=" & (-b - Sqr(b ^ 2 - 4 * a * c)) / (2 * a)
End IfEnd Sub

Answer 2

Private Sub Command1_Click()
Me.Cls
On Error GoTo P:
Dim a As Single, b As Single, c As Single, x1 As Single, x2 As Single
a = Val(Text1.Text)
b = Val(Text2.Text)
c = Val(Text3.Text)If (b * b - 4 * a * c) > 0 Then
x1 = (-b + Sqr((b ^ 2 - 4 * a * c))) / (2 * a)
x2 = (-b - Sqr((b ^ 2 - 4 * a * c))) / (2 * a)
Print "x1="; x1
Print "x2="; x2
ElseIf (b * b - 4 * a * c) = 0 Then
x = -b / 2 / a
Print "x="; x
Else
Print "无实数根。"
End If
P:
End Subxi 本来不想发源代码的。希望你能自己去图片上看····希望能对你有帮助