solve logarithmic inequalities with hp prime and khicas

HP-Prime CAS && Casio Graph 90+e ou TI-Nspire KhiCAS: Questions, documents, bugs, suggestions.
Federico Di Ceglie
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Inscription : sam. nov. 25, 2017 9:35 am

solve logarithmic inequalities with hp prime and khicas

Message par Federico Di Ceglie » mar. janv. 02, 2018 12:19 pm

Goodmorning everyone,
Parisse, do you know why when I solve log2(3+x)+log2(3-x)>=1 hp prime otput x>=-sqrt(7) and x<=sqrt(7) and with Khicas output x>=-sqrt(-e^1+36)\2 and x<=sqrt(-e^1+36)\2?

parisse
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Re: solve logarithmic inequalities with hp prime and khicas

Message par parisse » jeu. janv. 04, 2018 7:43 am

Can you enter the precise commandline (algebraic syntax)?
There is no log2 function in giac.

Federico Di Ceglie
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Inscription : sam. nov. 25, 2017 9:35 am

Re: solve logarithmic inequalities with hp prime and khicas

Message par Federico Di Ceglie » jeu. janv. 04, 2018 11:30 am

parisse a écrit :Can you enter the precise commandline (algebraic syntax)?
There is no log2 function in giac.
Both with prime and Khicas i use the template "log" of the two calculators, then I enter 2 as base of the logarithm.

parisse
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Re: solve logarithmic inequalities with hp prime and khicas

Message par parisse » jeu. janv. 04, 2018 12:27 pm

The log template of the nspire is not recognized, try log_2(3.0) then enter. Use natural logarithm or logb(x,b) instead.

Federico Di Ceglie
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Inscription : sam. nov. 25, 2017 9:35 am

Re: solve logarithmic inequalities with hp prime and khicas

Message par Federico Di Ceglie » jeu. janv. 04, 2018 2:40 pm

parisse a écrit :The log template of the nspire is not recognized, try log_2(3.0) then enter. Use natural logarithm or logb(x,b) instead.
With logb(x,b) Works, thank you very much

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