vb可以画多次曲线图么？

y=a*x*x*x+b*x*x+c*x+d (3)
我给你一个我做的例子，用4个点确定3次函数的
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Private Sub chazhi(x1, y1, x2, y2, x3, y3, x4, y4)
Dim f(4) As Double
For i = 1 To 4
ss(i, 4) = 1
Next i
For i = 1 To 3
ss(1, i) = x1 ^ (4 - i)
ss(1, 5) = y1
ss(2, i) = x2 ^ (4 - i)
ss(2, 5) = y2
ss(3, i) = x3 ^ (4 - i)
ss(3, 5) = y3
ss(4, i) = x4 ^ (4 - i)
ss(4, 5) = y4
Next i

f(2) = ss(2, 1) / ss(1, 1)
f(3) = ss(3, 1) / ss(1, 1)
f(4) = ss(4, 1) / ss(1, 1)
For i = 2 To 4
For j = 1 To 5
ss(i, j) = ss(i, j) - ss(1, j) * f(i)
Next j
Next i
f(3) = ss(3, 2) / ss(2, 2)
f(4) = ss(4, 2) / ss(2, 2)

For i = 3 To 4
For j = 2 To 5
ss(i, j) = ss(i, j) - ss(2, j) * f(i)
Next j
Next i
f(4) = ss(4, 3) / ss(3, 3)

For i = 4 To 4
For j = 3 To 5<