I don't recognize your equation for the cone because you've introduced a variable z

Isn't jeffguy's cone equation a reordering of equation 5 on this Wolfram page?

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"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^3: OT:Math problem: Grids and conical sections. by BrowserUk
in thread OT:Math problem: Grids and conical sections. by BrowserUk

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