Dúvida quanto a escrever a sentença de uma função por partes???

Lucas Farias shared this question 8 months ago
Needs Answer

Opa, tudo bom?!

Indo a questão haha. Topei com um problema ao tentar definir uma função por partes, ou seja, aquela em que podemos determinar condições a sua lei de formação (fiz como o apoio da ferramenta "Se"). Minha tentativa se resumiu a que a função assumi-se um dado valor em dado ponto... (fracassei), porém, quando repliquei o mesmo procedimento levando em conta uma desigualdade, ou noutras palavras, um intervalo... Funcionou! Assim, que tentei me aproveitar disso e prossegui da seguinte forma:

f(x) = Se(1<=x<=1,n,x^2)

Porém como visto na imagem, a ideia fica só na janela de álgebra hahaha (o que me fez levantar a ideia "sera que é realmente possível fazer isso?". Enfim, se alguém puder jogar luz a esta questão eu agradeço ;)


ao tentar escrever uma função por partes, mais especificamente ao tentar definir uma condição ao que não necessariamente representa um intervalo.

Best Answer
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I think that your definition is the issue :)

Are you sure that you want what you wrote, that is f(x) = If(1<=x<=1,n,x^2) ?

If so, GeoGebra (and whatever software) is not able to display a single point-pixel. You need to create the point (1,n) manually, and add it to your drawing. Anyway, the function (that might be better defined as f(x)=If(x==1,n,x^2) is well defined, and you can show e.g. discontinuity by calculating f(1), and the limits to 1 above and below. (try!)

Comments (4)

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1

I think that your definition is the issue :)

Are you sure that you want what you wrote, that is f(x) = If(1<=x<=1,n,x^2) ?

If so, GeoGebra (and whatever software) is not able to display a single point-pixel. You need to create the point (1,n) manually, and add it to your drawing. Anyway, the function (that might be better defined as f(x)=If(x==1,n,x^2) is well defined, and you can show e.g. discontinuity by calculating f(1), and the limits to 1 above and below. (try!)

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1

"If so, GeoGebra (and whatever software) is not able to display a single point-pixel. You need to create the point (1,n) manually, and add it to your drawing".

Ok. Now i'm disappointed haha...


"f(x)=If(x==1,n,x^2)"

== Wow *-*I didn't know this command.

I will use now haha


And finally. Thanks :)

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1

Here it's a simple file. Create the "hole" in the quadratic polynomial function, then create the point (1,n), depending on the slider.

Move the slider to show continuity/discontinuity of f(x).

Is this what you meant?

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I had done that, but the pixel idea would still be the desired. However, I still learned something so it was worth the try...

Thanks again ;)

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