tanh(x) undefined for x > 355

Pankaj Bhambhani shared this problem 4 months ago
In Progress

Apologies if this has been raised before. I did a quick google search and couldn't find an issue that matches this.

I'm trying to graph a tanh(x) function using GeoGebra Graphing Calculator, and it seems to only plot the curve for -infinity < x < 355. For x > 355 it returns as undefined.

My eventual goal is to graph tanh(3.5*x) from 0 to 365, but because of the above issue, the curve seems to only be drawn until x = 100.

Attaching a file with the above functions in case its helpful.

Comments (5)

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1

It seems OK to me. Please can you post a screenshot showing the problem?

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1

Hi,

Please find attached the screenshot

I graphed y = 100 + tanh(x) so that the curve isn't overlaid on the x-axis, allowing us to easy where the curve ends. You can see that geogebra says that y has an extremum at x = 353.88, which doesn't make sense.

Hope this helps. Happy to provide more information if necessary.

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1

Here is the URL for the above graph. https://www.geogebra.org/gr...

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2

Thanks, got it!

https://github.com/gwtproje...


You can use If(x>350,1,tanh(x)) as a workaround

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1

Thanks!

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