Re: When is exact mode not so exact? Message #5 Posted by Ronald Williams on 23 Feb 2012, 2:14 p.m., in response to message #4 by Bart (UK)
The exact result is 3 * sqrt(11). However, numeric (floating point) results are usually approximations. For this case sqrt(99) = sqrt(9*11) = sqrt(9)*sqrt(11) = 3*sqrt(11). 11's sqrt does not have a an simple exact floating point representation. This brings up the topic of accuracy or in this case I would say consistency of results. If accuracy is desired then I suggest reading this article
http://h20331.www2.hp.com/hpsub/downloads/HP_Calculator_eNL_01_January_2012.pdf
pages 2125 and pages 5051. Here is another
http://groups.google.com/group/comp.sys.hp48/browse_thread/thread/16ea6ddfb49e34eb/a53d3ab60541838d?lnk=gst&q=accuracy#a53d3ab60541838d
Does the 12th digit really matter or is it more important to know the capability and limitations of the tool you are using to solve the problem at hand?
Hopefully, the links are not broken, I usually don't post.
