What Geometric Shapes Do Equations Represent in Higher Dimensions?

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Homework Statement


What does the equation x^2 -2x + y^2 -2y + z^2 -2z + t^2 -2t + 4 = 0
represent in \Re^4? What does it represent in \Re^5? What does it represent in \Re^6?


Homework Equations


Complete the square.


The Attempt at a Solution


After completing the square (letting 4 = 1 + 1 + 1 + 1), the equation becomes

(x-1)^2 + (y-1)^2 + (z-1)^2 + (t-1)^2 = 0

In \Re^4, the equation represents the coordinate (1,1,1,1). I have a hard time visualizing the cases for \Re^5 and \Re^6. I figure that it should be easier to visualize knowing that in \Re^4, we have a fixed point.

Of course I have deduced that we will get a line and a plane in \Re^5 and \Re^6, respectively, by looking at smaller cases. But what is the exact configuration and how do I see it?
 
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snipez90 said:
What does it represent in \Re^5? What does it represent in \Re^6?

Of course I have deduced that we will get a line and a plane in \Re^5 and \Re^6, respectively, by looking at smaller cases. But what is the exact configuration and how do I see it?

Hi snipez90! :smile:

"a line and a plane" is the answer! :smile:

If you want to give the exact equation, the line, for example, would be x=y=z=t=1 (and w = anything). :wink:
 
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