Inequality : Control display above x axis

lewws shared this question 3 months ago
Answered

Hi,

I have inequalities x>3, x <= 5 and 3<x<= 5 on the number line display.

Can we have control to display the three inequalities at different height above x axis?

File at https://www.geogebra.org/m/t4q8zy8z

Thanks

Comments (7)

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Hi lewws

Nice to meet you.

My solution is not mathematically, but she works (with Locus()).

Note: I'm not sure: but I think x<= 5 must be an area (left from x=5), not a horizontal ray (compare b with bugTest). If I enter in GGB5.0.579 or GGB6.0.579: x<5, then result is an area and I think it is correct. It is mysterious to me how an inequality something like a function (a(x)=0x, x<=5) could arise in your file.

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Hi Raymond,

Thanks for quick answer!

Good idea on the locus.. I may have to use it for now, and add the endpoints with hollow circle or solid dot, with some code to check the inequalities.


About function (a(x)=0x, x<=5), I am not sure how it generated too, from the system.


Best regards,

lewws.

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cool

try shifting point(a,0) and point(a,1) with style depending of a(<point>) is true or false

Files: foro.ggb
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Thank you too!

point(a,0) and point(a,1) give both ends, good technique.

I get it now why a(<point>) true or false , to make full or hollow circle!

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Implemented

https://www.geogebra.org/m/t4q8zy8z


Thank you both!

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Also tried a more tedious approach which require parsing the inequality expressions and using Unicode to extract the type of inequality symbol and direction of the inequalityhttps://www.geogebra.org/m/q94pssh5

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Thanks rami and mathmagic for sharing the above and enabling me to improve on the student resource at

Solving Simultaneous Linear Inequalities

https://www.geogebra.org/m/rsjvsqpp

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