求助VB编程达人帮忙编写一个程序嘛~

Question

【实验6-4】利用Function过程计算下列分段函数的值。
Cos2x （0 > x ）
f(x)= Int(6x2 -5x+1) ( 0≤x≤3 )
e3-x ( 3＜x )
调用该Function过程，计算f(a)+f(2+f(b))的值。其中a、b用InputBox函数输入。

Answer 1

Private Function Fdhs(x As Single) As Single
If x < 0 Then
Fdhs = Cos(2 * x)
ElseIf x <= 3 Then Fdhs = Int(6 * x * x - 5 * x + 1)
Else: Fdhs = 2.71828 ^ (3 - x)
End If
End Function
Private Sub Command1_Click()
Dim x As Single
Dim y As Single
x = Val(InputBox("请输入a的值"))
y = Val(InputBox("请输入b的值"))
Print "f(a)+f(2+f(b))=" & Fdhs(x) + Fdhs(2 + Fdhs(y))
End Sub

Answer 2

private function f(x) as single
if x<0 then
f=cos(2*x)
elseif x<=3 then
f=int(6*x^2-5*x+1)
else
f=e^(3-x)
end if
end sub

你写的式子可能有些不准确，我猜着写的，你看对不对.不懂可以问我