Re: plotting even function

[Geraint Paul Bevan]

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John B. Thoo wrote:
| Hi.  I hope that I'm not embarrassing myself by asking the following.
|
| I believe that
|
|        3       2/3    1
|   y = --- (2 x)    + ---
|        4              2
|
| is an even function, yet
|
| x = -1:0.04:1;
| plot (x, 0.75 * (2 .* x).^(2 / 3) + 0.5)
|
| is not symmetrical about the y-axis.  What is wrong with my thinking?
|
| TIA.
| ---John.


x^(2/3) is not an even function,

octave:1> [ (+8)^(2/3) ; (-8)^(2/3) ]
ans =

~    4.0000 + 0.0000i
~   -2.0000 + 3.4641i

so nor is the function which you are plotting.

- --
Geraint Bevan
http://homepage.ntlworld.com/geraint.bevan

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