Homogeneous nonlinear function

[matt grime]

The example/non-example of sqrt(x^2+y^2) was not necessarily given by anyone before I posted the same.

post 4, initial guess x^2+y^2, then a first correction to the square root of this, then the assertion that this is close but doesn't quite work, then the comment that the OP might be able to think of a better example (given this one, implicitly, and explicitly by taking note of the title of his/her own thread).

 

[cryptic26]

post 4, initial guess x^2+y^2, then a first correction to the square root of this, then the assertion that this is close but doesn't quite work, then the comment that the OP might be able to think of a better example (given this one, implicitly, and explicitly by taking note of the title of his/her own thread).

If you are implying that your statement "like f(x,y)=x^2+y^2, then f(kx,ky)=k^2f(x,y), so that won't do... but can we make it better? Next guess would be to take g(x) as sqrt(f(x)), but no, that gives |k|, not k"

was meant to be sqrt(x^2+y^2), then it is obvious only after your most recent clarification.

 

[cryptic26]

There is a line in Red Dwarf that is apposite, something along these: I realize that is the same thing, but it seemed important enough for me to say it twice.

Since you've taken it upon yourself to inform at least two people that they are confused and incorrect, when they aren't, then reinforcing the message seems like a good thing.

Although a question can be the beginning of wisdom, a debate can be the reflection of one's ego.

Telling people that they are confused is not something that I usually do - not unless I intend to match their impoliteness (That is other way of saying that you came across as impolite.)

 

[matt grime]

If you are implying that your statement "like f(x,y)=x^2+y^2, then f(kx,ky)=k^2f(x,y), so that won't do... but can we make it better? Next guess would be to take g(x) as sqrt(f(x)), but no, that gives |k|, not k"

was meant to be sqrt(x^2+y^2), then it is obvious only after your most recent clarification.

So if i declare f(x)=x^2+y^2, and then declare g(x) to be the square root of f(x), in what way it that not sqrt(x^2+y^2)?

 

[cryptic26]

So if i declare f(x)=x^2+y^2, and then declare g(x) to be the square root of f(x), in what way it that not sqrt(x^2+y^2)?

Actually, I am hardly doing the homework, I am just a visitor to this forum. But, probably you are just used to having your own way. I think you are just a big headed , ill tempered person. There is an old saying that if you throw a stone at swamp, you will get your shirts dirty. And arguing with you is going to only waste my time. Period.

 

[quantster]

So if i declare f(x)=x^2+y^2, and then declare g(x) to be the square root of f(x), in what way it that not sqrt(x^2+y^2)?

Very intereting posts and emotions. To be consistent with the original notations of matt, he could have written g(x) to be square root of f(x,y) and not f(x), as he defined f(x,y) and not f(x) to be x^2+y^2.

 

[cryptic26]

Very intereting posts and emotions. To be consistent with the original notations of matt, he could have written g(x) to be square root of f(x,y) and not f(x), as he defined f(x,y) and not f(x) to be x^2+y^2.

I was not planning to write but quantster raised a good point. In fact that was the beginning of the confusion.

In the future make sure to use consistent notations instead of assuming that people shall get some vibe from you and be able to read your mind.