1、tanx的（VBA）计算程序

Dim A(1 To 100) As Double

Dim Pi As Double

Private Sub CommandButton1_Click()

On Error GoTo 100

Sheet1.Cells(5, 1) = ""

x = Sheet1.Cells(1, 1)

n = Sheet1.Cells(1, 2)

Pi = 3.141592654

y = x - Int(x / Pi) * Pi

For i = 1 To n + 1

A(i) = 0

Next i

A(1) = y / 2 ^ n

For i = 1 To n

A(i + 1) = 2 * A(i) / (1 - A(i) ^ 2)

Next i

Sheet1.Cells(5, 1) = A(n + 1)

GoTo 200

100 Sheet1.Cells(5, 1) = "error"

200 End Sub

2、Cosx的（VBA）计算程序

Dim AA(1 To 100) As Double

Dim Pi As Double

Private Sub CommandButton1_Click()

On Error GoTo 100

Sheet2.Cells(2, 1) = ""

x = Sheet2.Cells(1, 1)

m = Sheet2.Cells(1, 2)

Pi = 3.141592654

y = x - Int(x / Pi / 2) * Pi * 2

For i = 1 To m + 1

AA(i) = 0#

Next i

AA(1) = 1 - y ^ 2 / 2 ^ (2 * m + 1)

For i = 1 To m

AA(i + 1) = 2 * AA(i) ^ 2 - 1

Next i

Sheet2.Cells(2, 1) = AA(m + 1)

GoTo 200

100 Sheet2.Cells(2, 1) = "error"

200 End Sub