Solving Surface Equation Homework

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SUMMARY

The discussion focuses on deriving the mathematical representation of a surface equation after rotation, specifically transitioning from Cartesian to polar coordinates. The general equation for a circle is established as y² + x² = f²(x), where f(x) represents the radius. The transformation into polar coordinates is confirmed with the equations x = r*cos(Θ) and y = r*sin(Θ), leading to the identity x² + y² = r². This confirms the relationship between the radius and the surface equation.

PREREQUISITES
  • Understanding of Cartesian and polar coordinate systems
  • Familiarity with surface equations and their representations
  • Knowledge of trigonometric functions and their applications
  • Basic algebraic manipulation skills
NEXT STEPS
  • Study the derivation of surface equations in three-dimensional geometry
  • Explore the applications of polar coordinates in various mathematical contexts
  • Learn about the properties of circles and their equations in different coordinate systems
  • Investigate the relationship between trigonometric identities and geometric shapes
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Students studying mathematics, particularly those focusing on geometry and calculus, as well as educators seeking to clarify concepts related to surface equations and coordinate transformations.

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Homework Statement



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Homework Equations





The Attempt at a Solution



It seems very obvious that after rotation, it becomes a circle, so how to write it out mathematically?

That I don't know the general equation of a surface.
Is [itex]y^2+x^2=f^2(x)[/itex] the answer?


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Yes, this is the general equation for a circle

[tex]f(x)²=x²+y²=r²[/tex]

As seen in the figure, f(x)=radius

And from polar coordinates you can get the equation:

[tex]x=r*cos(\Theta)[/tex]
[tex]y=r*sin(\Theta)[/tex]
[tex]x²+y²=r²(cos²(\Theta)+sin²(\Theta))=r²[/tex]
 

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