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#1 2005-12-28 08:16:37
- kdria041
- Novice
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Curve Equation
0 0
1 0
2 0
3 10
4 83
5 170
6 300
7 500
8 750
9 1150
10 1500
11 1750
12 1800
Can anyone give me the formula for this plot? The numbers are not absolute, as they were taken off a small graph, so a formula that would aproximate this curve is ok. THANKS!
asympyotes 0, 1800
This is the curve for which I need an equation:
#2 2005-12-28 11:01:48
- John E. Franklin
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Re: Curve Equation
Here is a silly answer that uses operators that are probably disallowed in algebra in this fashion for some reason or other.
y=0(x<3) + (3 ≤ x<11)(1800/(11-3))(x-3) + (x ≥ 11)1800
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#3 2005-12-28 17:00:31
- MathsIsFun
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Re: Curve Equation
The tanh(x) function has two horizontal asymptotes, it could be adapted possibly.
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#4 2005-12-28 23:46:03
- krassi_holmz
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Re: Curve Equation
arctan(x) also has two horizontal asymptotes.
But I think that these functions cannot be adapted for this graph, because it is not symmetric.
IPBLE: Increasing Performance By Lowering Expectations.
#5 2005-12-29 23:43:13
- mathsyperson
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Re: Curve Equation
kdria041 wrote:
Why not this for solution?:
if:3<x<12 y=((1/logx^3)+1)*x^3
kdria posted that meaning to reply to this topic, but accidentally starting a new one instead.
You can reply using the 'post reply' button. ;)
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It wanted to be normal.
#6 2005-12-30 02:12:30
- seerj
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Re: Curve Equation
krassi_holmz wrote:
arctan(x) also has two horizontal asymptotes.
But I think that these functions cannot be adapted for this graph, because it is not symmetric.
Yes I quote him! You can use arctan(x) by creating your own function
For example try to plot a function like this:
2*atan(x-3)+3
#7 2005-12-30 02:16:45
- seerj
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Re: Curve Equation
seerj wrote:
krassi_holmz wrote:
arctan(x) also has two horizontal asymptotes.
But I think that these functions cannot be adapted for this graph, because it is not symmetric.Yes I quote him! You can use arctan(x) by creating your own function
For example try to plot a function like this:
2*atan(x-3)+3
Or wait also tanh(x) is good. I think is perfect for your case
Try to plot it
tanh(x-3/5)+1
Last edited by seerj (2005-12-30 02:21:16)
#8 2005-12-30 08:25:16
- krassi_holmz
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Re: Curve Equation
Yes, yes.
And seerj's curves are close.
IPBLE: Increasing Performance By Lowering Expectations.