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john229
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Graphing an astroid curve

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50G Graphing calculator

the function I would like  to graph is  x^(2/3) +y^(2/3) = 4

Is my difficult the fact that the exponent is not n integer?

Thank you

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mdklassen
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>  I would like  to graph is  x^(2/3) +y^(2/3) = 4

 

What happens if you graph:   2/3*log(x) + 2/3*log(y) = log(4) ?

Or:  log(x) + log(y) = 1.5* log(4) ?

 

By the way, is this a "homework" assignment?

If so, please give credit to this forum for helping you with your school-work. :generic:

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Jan_D
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@john229 wrote:

the function I would like  to graph is  x^(2/3) +y^(2/3) = 4

Is my difficult the fact that the exponent is not n integer?

Thank you


Hello,

 

What did you choose forType in 2D/3D settings? Function or Conic?

 

Your equation is not in the form of a function, because a function is in the form:  y=f(x)

 

In my opinion for Conic plotting the exponent of y has to be 1 or 2, so it is not usable either.  

 

But you can rewrite your equation in the form of a function:

 

y=[4-x^(2/3)]^3/2

 

and this you can plot.

 

 

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mdklassen
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>   log(x) + log(y) = 1.5* log(4)

 

Thus,   log(y) = 1.5* log(4) - log(x)

 

Thus, y = exp((1.5*log(4)-log(x)))

 

to cast it as y = function(x)

 

 

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mark4flies
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The log of a sum is not equal to the sum of the logs. The log of a product is the sum of the logs.

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mdklassen
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Indeed.  :generic:

 

If it was a "homework" question, then copying an incorrect answer from the Internet will be marked as incorrect.

Moral: learn the material -- don't believe everything you read on the Internet.  :LaughingTears:

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