Public Function pr_e(x As Double, Точность As Double) As Double
result=0;
fact=1;
step=2;

if abs(x)<1 then
while Abs((x^fact)/fact)>Точность
  result=result+((-1)^step) *(x^fact)/fact;
  fact=fact+2;
wend
endif

if x<=-1 then
***

end sub

Public Function arctangens(x As Double, Точность As Double) As Double
Dim result1 As Double
Dim result2 As Double
Dim pr_result1 As Double
Dim pr_result2 As Double

result1 = -3.141592654 / 2 - 1 / x
result2 = x
result3 = 3.141592654 / 2 - 1 / x
pr_result13 = -1 / x
pr_result2 = x
k = 3

If x <= -1 Then
    While Abs(pr_result13) > Точность
        pr_result13 = -pr_result13 * ((k - 2) / ((x ^ 2) * k))
        result1 = result1 + pr_result13
        k = k + 2
    Wend
arctangens = result1

ElseIf x < 1 Then
    While Abs(pr_result2) > Точность
        pr_result2 = -pr_result2 * (((k - 2) * x ^ 2) / k)
        result2 = result2 + pr_result2
        k = k + 2
    Wend
arctangens = result2

Else
    While Abs(pr_result13) > Точность
        pr_result13 = -pr_result13 * ((k - 2) / ((x ^ 2) * k))
        result3 = result3 + pr_result13
        k = k + 2
    Wend
arctangens = result3
End If
End Function