Ec ||A||I= <=1, i 
, .
Call zeidel(eps, x, n)
For i = 1 To 4
x(i) = 0: Next i: n = 0
Do: n = n + 1: l = False
For i = 1 To 4: x0(i) = x(i): Next i
For i = 1 To 4: x(i) = b(i) / a(i, i)
For j = 1 To i 1: x(i) = x(i) - a(i, j) / a(i, i) * x0(j): Next j
For j = i + 1 To 4: x(i) = x(i) - a(i, j) / a(i, i) * x(j): Next j
If Abs(x(i) - x0(i)) > e Then: l = True: End If: Next i
Loop Until Not l: End Sub
. .
:
-
-
-
a b .
:
xn = PrN(a, b, eps, n)
k = 1: s1 = 0: n = 0
Do
s = s1: k = k * 2: n = n + 1
dx = (b - a) / k
s1 = 0
For x = a To b - dx + e Step dx
s1 = s1 + f(x)
Next x
s1 = dx * s1
Loop Until Abs(s - s1) <= e
PrN = s1
End Function
. .
(, )
:
-
-
a b .
:
xm = PrM(a, b, eps, n)
k = 1: s1 = -1: n = 0
Do
s = s1: k = k * 2: n = n + 1
dx = (b - a) / k
s1 = 0
For x = a + dx To b + e Step dx
s1 = s1 + f(x)
Next x
s1 = dx * s1
Loop Until Abs(s - s1) <= e
PrM = s1
End Function
. .
:
xt = Trap(a, b, eps, n)
Dim k As Currency
Dim s, s1, x, dx As Double
k = 1: s1 = -1: n = 0
Do
s = s1: k = k * 2: n = n + 1
dx = (b - a) / k
s1 = (f(a) + f(b)) / 2
For x = a + dx To b - dx + e Step dx
s1 = s1 + f(x): Next x
s1 = dx * s1
Loop Until Abs(s - s1) <= e
Trap = s1: End Function
f(x). .
Function Dix(a, b, e, n) As Double
Dim x1, x2 As Double
n = 0
While (b - a) > e
n = n + 1
x1 = a + 0.25 * (b - a)
x2 = a + 0.75 * (b - a)
If f(x1) < f(x2) Then
b = x2
Else
a = x1
End If
Wend
Dix = (a + b) / 2
End Function
28. f(x). .
:
1) f(x1), x1=a+0,382(b-a)
2) f(x2), x2=b-0,382(b-a)
3) : (a;x2) 1 (x1;b) 2 , .
4) 1 x1, 2 x2, , 0,382 . f(x), 3 , 
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Function Gold(a, b, e, n) As Double
Dim x1, x2 As Double: n = 0
While (b - a) > e: n = n + 1
x1 = a + 0.318 * (b - a)
x2 = a + 0.682 * (b - a)
If f(x1) < f(x2) Then: b = x2: Else: a = x1: End If
Wend: Gold = (a + b) / 2: End Function
