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[HP-PRIME CAS] inequations - Printable Version

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[HP-PRIME CAS] inequations - CompSystems - 11-02-2013

see screenshot at the end of the next picture

solve((ABS(ABS(2*x+1)-5))>2,x); [ENTER] => { -4>x,x>-2 AND 1>x,x>3}

Re: [HP-PRIME CAS] inequations - Han - 11-02-2013

Both the HP Prime and the TI nSpire produce correct answers. They just return slightly different representations of the same solution.

x>-2 AND x<1 means the same as -2<x<1

A or B or C is the same as A or (B or C).

Re: [HP-PRIME CAS] inequations - CompSystems - 11-02-2013

AS(x>-2 AND x<1) == (-2<x<1) Why -2<x<1 => 0 // BUG?

Edited: 2 Nov 2013, 11:03 p.m. after one or more responses were posted

Re: [HP-PRIME CAS] inequations - Han - 11-02-2013

The inequality > and < have higher priority than AND. So

x>-2 AND x<1 is actually (x-2) AND (x<1) … not to be confused with x> (-2 and x) < 1 -- which would not make much sense.

Also, the result returns a symbolic object which embeds AND -- which is very different from a result which evaluates binary operation.