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#1 2006-01-06 00:49:42
- 3d_guru
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- Registered: 2006-01-02
- Posts: 5
derivative..
again..i've uploaded the picture because it's easier to write it in Mathematica..
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#2 2006-01-06 01:21:10
- krassi_holmz
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- Registered: 2005-12-02
- Posts: 1,905
Re: derivative..
If you use Mathematica it's easy.
IPBLE: Increasing Performance By Lowering Expectations.
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#3 2006-01-06 01:25:50
- krassi_holmz
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- Registered: 2005-12-02
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Re: derivative..
Put the following code:
Print["The Function:"]
f[x_]:=((x^2)Log[x])/ \[ExponentialE]
f[x]
Print["The Derivate:"]
f'[x]
Print["The roots:"]
Solve[f'[x] == 0, x]IPBLE: Increasing Performance By Lowering Expectations.
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#4 2006-01-06 01:29:52
- krassi_holmz
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- Registered: 2005-12-02
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Re: derivative..
And you can include Plots:
Plot[f[x], {x, 0, 10}, AxesLabel -> {x, f[x]}]
Plot[f[x], {x, 0, 1}, AxesLabel -> {x, f[x]}]
Plot[f'[x], {x, 0, 10}, AxesLabel -> {x, f'[x]}]
Plot[f'[x], {x, 0, 1}, AxesLabel -> {x, f'[x]}]IPBLE: Increasing Performance By Lowering Expectations.
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#5 2006-01-06 01:39:34
- krassi_holmz
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- Registered: 2005-12-02
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Re: derivative..
Here is the program:
(demonstrates the power of Mathematica once again)
Last edited by krassi_holmz (2006-01-06 01:41:21)
IPBLE: Increasing Performance By Lowering Expectations.
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#6 2006-01-06 01:59:01
- 3d_guru
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- Registered: 2006-01-02
- Posts: 5
Re: derivative..
hey thanx krassi_holmz..didn't know Mathematica was so powerfull.
oh man and the code is so simple, that's great!
thanx again..i appreciate it
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#7 2006-01-06 02:14:38
- krassi_holmz
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- Registered: 2005-12-02
- Posts: 1,905
Re: derivative..
Haven't you read Mathematica help?
It's hundred times powerful than this. It's just a simple example.
Last edited by krassi_holmz (2006-01-06 02:15:32)
IPBLE: Increasing Performance By Lowering Expectations.
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#8 2006-01-08 09:20:49
- God
- Member
- Registered: 2005-08-25
- Posts: 59
Re: derivative..
Derivative =0
x^2 = 0, x = 0
or
2xlnxe - lnx = 0
lnx(2xe-1) = 0
lnx = 0 or 2ex - 1 - 0
x = 1 or x = 1/(2e)
So, horizontal tangents occur at
x = 1
x = 1/(2e)
x = 0
Double check that the second derivative is never equal to 0 for each of those points... when it does, it isn't an extrema
Last edited by God (2006-01-08 09:21:56)
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