<![CDATA[welding a piecewise function together at a point?]]>
https://help.geogebra.org/topic/welding-a-piecewise-function-together-at-a-point
Tue, 26 Mar 2019 21:16:43 +0000Mon, 25 Mar 2019 19:46:18 +0000Zend_Feed<![CDATA[Hi Mads! The cut of the domains of f and g is empty. In your first definition f has no value at x=2. Greetings mire2]]>
https://help.geogebra.org/topic/welding-a-piecewise-function-together-at-a-point#comment-258214
Tue, 26 Mar 2019 06:58:41 +0000<![CDATA[Why not defining both as a single piecewise function? h(x) = If(-4 < x < 2, 1 / 2 x + 5, x ≥ 2, x² - 7x + 16)]]>
https://help.geogebra.org/topic/welding-a-piecewise-function-together-at-a-point#comment-258236
Tue, 26 Mar 2019 08:02:30 +0000<![CDATA[Because I need to test if f(j) = g(j) or f'(j) not equel g'(j) when j = 2. So is that possible?]]>
https://help.geogebra.org/topic/welding-a-piecewise-function-together-at-a-point#comment-258252
Tue, 26 Mar 2019 08:43:30 +0000<![CDATA[Hi Mads! :smile: Ok, another try. Yes, you can test it that way, but ... f(j)=g(j) means, that j ∈ dom(f) ∩ dom(g) solving the equation But in your given example dom(f) ∩ dom(g) = ∅, so there is no j solving the equation. What you have to do is to proof if LimitBelow(f,2)==LimitAbove(g,2). Edit: Hmm, that doesn't work, because the limits are "undefined", but with Simona's function h it works fine. Greetings mire2]]>
https://help.geogebra.org/topic/welding-a-piecewise-function-together-at-a-point#comment-258256
Tue, 26 Mar 2019 10:29:13 +0000<![CDATA[try a single piecewise function and LimitAbove( <Function>, <Value> ) LimitBelow( <Function>, <Value> )]]>
https://help.geogebra.org/topic/welding-a-piecewise-function-together-at-a-point#comment-258258
Tue, 26 Mar 2019 09:49:44 +0000<![CDATA[That should work in theory, but I define h(x), h(x) = If(-4 < x < 2, 1 / 2 x + 5, If(x ≥ 2, x² - 7x + 16)) Then the limit is undefined. But the graph is "connected" graphically at x = 2. So what am I doing wrong?]]>
https://help.geogebra.org/topic/welding-a-piecewise-function-together-at-a-point#comment-258268
Tue, 26 Mar 2019 11:40:12 +0000<![CDATA[the correct syntax is h(x) = If(-4 < x < 2, 1 / 2 x + 5, x ≥ 2, x² - 7x + 16) use it like in attached]]>
https://help.geogebra.org/topic/welding-a-piecewise-function-together-at-a-point#comment-258278
Tue, 26 Mar 2019 13:21:47 +0000<![CDATA[Many thanks for your answer, Sir :) Then my final questionaire is if I want to test whether (1 / 2 x + 5)' and (x² - 7x + 16)' at x = 2 er different ? meaning 1 / 2 x + 5)' notequal (x² - 7x + 16)' ?? and (1 / 2 x + 5)==(x² - 7x + 16) ? At the given conditions. Is that that possible?]]>
https://help.geogebra.org/topic/welding-a-piecewise-function-together-at-a-point#comment-258280
Tue, 26 Mar 2019 13:43:06 +0000<![CDATA[type h'(x) or derivative(h) then use limitabove(h',2) and limitbelow(h',2)]]>
https://help.geogebra.org/topic/welding-a-piecewise-function-together-at-a-point#comment-258304
Tue, 26 Mar 2019 21:14:25 +0000<![CDATA[Thank you Very much. Your input helped me get the bugs of out my "programming " :) Have a nice day/evening where you are in the world :D]]>
https://help.geogebra.org/topic/welding-a-piecewise-function-together-at-a-point#comment-258308
Tue, 26 Mar 2019 21:16:44 +0000