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#2 2006-01-07 00:21:10
- krassi_holmz
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Re: derivative..
If you use Mathematica it's easy.
IPBLE: Increasing Performance By Lowering Expectations.
#3 2006-01-07 00:25:50
- krassi_holmz
- Real Member
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Re: derivative..
Put the following code:
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.
#4 2006-01-07 00:29:52
- krassi_holmz
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Re: derivative..
And you can include Plots:
Code:
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.
#5 2006-01-07 00:39:34
- krassi_holmz
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Re: derivative..
Here is the program:
(demonstrates the power of Mathematica once again)
Last edited by krassi_holmz (2006-01-07 00:41:21)
IPBLE: Increasing Performance By Lowering Expectations.
#7 2006-01-07 01:14:38
- krassi_holmz
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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 (2006-01-07 01:15:32)
IPBLE: Increasing Performance By Lowering Expectations.
#8 2006-01-09 08:20:49
- God
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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 (2006-01-09 08:21:56)