Question about Texas Instruments TI-89 Calculator

When I graph y = square root of x, or cube root of x, or any root of x, I get an error message saying undefined variable. I don't understand this.

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• Anonymous Mar 31, 2014

need to multiply roots with variables and exponents and see them in the same way

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• Contributor

I have a TI-89 Titanium and I have experienced the same problem. HERE IS HOW TO FIX IT:

Goto " MODE " and scroll down the options until you get to
" COMPLEX FORMAT " change that option to " RECTANGULAR " and press ENTER until you exit out of the " MODE " screen. (very important that you press ' enter ' until you exit because if you don't, it will not save your changes. )

Posted on Mar 15, 2009

I had the same problem, when the term under the root could be <0 the complex mode can't be polar. Changing to another mode graphed it.

Posted on Feb 14, 2008

D(x) = sqrt 3x/2

Posted on Nov 29, 2007

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Posted on Jan 02, 2017

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I have a manual in another language than English, so I do no know exactly or remotely what procedure you refer to, but I have recreated an instance where one gets the error you talk about. I give you the picts. When I enter [Diamond][Graph] I get the following message.

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Hope it clarifies things.

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