Geogebra gives wrong derivative for following function f(x)=sin(x)^cos(x

kaisa123 shared this question 1 month ago
Answered

Geogebra gives wrong derivative for following simple function f(x)=sin(x)^cos(x). It gives f'(x)=cos(x)(I have Lenovo and windows 10). My sister's (macbook) gives the right derivative f'(x)=-ln(sin(x))*sin^(cos(x)+1)+cos(x)^2*sin(x)^(cos(x)-1).

Comments (12)

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GG Classic 5 and 6 both give the right derivate. The Graphic Calculator produces the right graph for it. So what do you mean with "Geogebra produces"? At least we know your sister is using a macbook and you're using windows 10, but which version or app of GeoGebra are you using? This is what GG 5 & 6 Classic give me on a my laptop with win10.

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I confirm that

ggb6n.jpg - before pressing Enter

ggb6na.jpg - after pressing Enter

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First, I just said I got the right derivate and asked about what version kaisa was using, since there was just a description and no file nor screen capture picture.

Second I us the same GG5 as you, but the position of cos in the equation is different.

For the different result in GG6 I've got no explanation.

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In the CAS window

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and in Geogebra 6 too

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efectivamente el CAS transforma cualquier expresion que resulte sin(x)^cos(x) en sin(x)^1 incluso la expresion sin(x)^(cotan(x)*sin(x)) es transformada

creo recordar que este bug ya estuvo entre nosotros hace seis meses y parece que ahora vuelve

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This is definitely a bug. It is at least in GG5, GG6, GeoGebra CAS and Calcultor Suite.

M

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Please try v590

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problem persist in ver5

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also online

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Sorry, my mistake. Should be in v591

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v591 online now

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Thanks, works OK in GeoGebra 5.

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