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Hello everyone, I stumbled over a zero-Point Problem... I attached a Picture of my Problem. I wanted to calculate the Zero-Point of f(x)=-e^(x/33)+6. The Programm says that there are no "real" Zero Points. So I played around a Little bit and found out that when the Exponent reaches 0.091 ->0.09 the error occurs. Do you guys have any guesses or did I found a bug in here? Thanks  Edited by moderator 20 May 2016 21:51:44(UTC)
| Reason: marked ad solved
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  Rank: Advanced Member Groups: Registered
Joined: 23/12/2011(UTC) Posts: 319   Location: italy Was thanked: 109 time(s) in 93 post(s)
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It is not a bug. You simply set correctly
Tools--> Options --> Calculation --> Roots (range)
sergio
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 2 users thanked PompelmoTell for this useful post.
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on 18/02/2016(UTC), on 18/02/2016(UTC)
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Rank: Newbie
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Joined: 18/02/2016(UTC)
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Thank you very much!
I am new to the Programm and did not know (and why?) there were an upper and lower range of the roots.
The topic can be deleted..
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 Rank: Guest
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Joined: 04/07/2015(UTC) Posts: 6,866  Was thanked: 981 time(s) in 809 post(s)
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No, don't delete the topic. Answer is correct, it doctored the case.
Some very flat functions may not find roots even in advanced CAS [Computer Algebra System].
Smath 32 bits, not 64 extended floating point does not help either.
More generally, computing machinery are limited by their "ulp" [Unit in Last Place].
"ulp" => read as popular "granularity". Between two machine numbers to close together
the system zigzag eternally, but they all have an internal error detect.
"No real root" is a typical Smath error message.
Jean
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