Why Doesn't My 2-Sphere Graph Correctly in GraphCalc?

  • Thread starter Thread starter yourdadonapogostick
  • Start date Start date
  • Tags Tags
    Graph
AI Thread Summary
The user attempted to graph a 2-sphere in GraphCalc using the equations z=√(-x²-y²+9) and z=-√(-x²-y²+9), expecting a sphere centered at the origin with a radius of 3. However, the graph did not appear as intended, particularly near the xy-plane where the slope becomes steep. The issue arises because GraphCalc evaluates function values on a limited grid, leading to inaccuracies in rendering the sphere. Despite the initial failure, the sphere is present but distorted due to these graphical limitations. Understanding the program's constraints can help improve future attempts at graphing complex shapes.
yourdadonapogostick
Messages
270
Reaction score
1
i attempted to graph a 2-sphere on graphcalc and it wouldn't work. the equations had to be in terms of z, so i had to use: z=\sqrt{-x^2-y^2+9} and z=-\sqrt{-x^2-y^2+9}. i thought that would give me a 2-sphere at the origin with a radius of 3, but it didn't. i got:[PLAIN]http://photobucket.com/albums/a192/YoDizzle/th_almostsphere.bmp.[/URL] what did i do wrong?

the split is along the x y plane. if it matters, this is my first try at using graphcalc.
 
Last edited by a moderator:
Mathematics news on Phys.org
You got a sphere. It just breaks down near the xy-plane, because the approximations get fuzzy as the slope becomes very large. Your program only evaluates the function value on a small grid of points.
 

Thread 'Fermat's Last Theorem'

Fermat's Last Theorem has long been one of the most famous mathematical problems, and is now one of the most famous theorems. It simply states that the equation $$ a^n+b^n=c^n $$ has no solutions with positive integers if ##n>2.## It was named after Pierre de Fermat (1607-1665). The problem itself stems from the book Arithmetica by Diophantus of Alexandria. It gained popularity because Fermat noted in his copy "Cubum autem in duos cubos, aut quadratoquadratum in duos quadratoquadratos, et...
View full post »

Thread 'What Exactly is Dirac’s Delta Function? - Insight'

Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In Dirac’s Principles of Quantum Mechanics published in 1930 he introduced a “convenient notation” he referred to as a “delta function” which he treated as a continuum analog to the discrete Kronecker delta. The Kronecker delta is simply the indexed components of the identity operator in matrix algebra Source: https://www.physicsforums.com/insights/what-exactly-is-diracs-delta-function/ by...
View full post »
Thread 'Imaginary Pythagorus'

Thread 'Imaginary Pythagorus'

I posted this in the Lame Math thread, but it's got me thinking. Is there any validity to this? Or is it really just a mathematical trick? Naively, I see that i2 + plus 12 does equal zero2. But does this have a meaning? I know one can treat the imaginary number line as just another axis like the reals, but does that mean this does represent a triangle in the complex plane with a hypotenuse of length zero? Ibix offered a rendering of the diagram using what I assume is matrix* notation...
View full post »

Similar threads

B Fractional/decimal powers
Replies
10
Views
2K
I Transforming coordinates between Cartesian and spherical
Replies
1
Views
2K
B Wolfram Alpha's Why the 2 i π n?
Replies
3
Views
2K
Triple Integral To Find Volume Between Cylinder And Sphere
Replies
2
Views
2K
MHB Why I Get X & Y Mixed Up When Plotting Graphs
Replies
3
Views
2K
B Invariant under rotation: Banal, obvious, or noteworthy?
Replies
2
Views
2K
MHB Calculating Radius of Circular Section from Sphere and Plane Intersection
Replies
2
Views
3K
MHB Can I Graph a Semicircle By Hand?
Replies
4
Views
2K
MHB How to use change of variables technique here?
Replies
2
Views
1K
Find the constrained maxima and minima of ##f(x,y,z)=x+y^2+2z##
Replies
2
Views
1K

Hot Threads

Recent Insights

Back
Top