Recent content by DorumonSg

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    How to define a solid cyclinder or any solid objects parametrically?

    Oh and another question. According to the notes my teacher gave me, The equation of a circle is r^2 - x^2 - y^2 = 0 where r is the radius. While the equation for a circle disk(half space) is r^2 - x^2 - y^2 >= 0 Why is this so? And why does half space mean in 2D?
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    How to define a solid cyclinder or any solid objects parametrically?

    How to define a solid cyclinder or any solid objects parametrically? I can't figure out what do I do with the z axis for example a Cylinder : x = 0.5*cos(theta) y = sin(theta) 0*pi <= theta <= 2*pi This will make an eclipse. But wad about z? I know we have to stretch z to the...
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    Understanding the Parametric Equation for a Sphere

    Thanks a lot. I think I got it already. I haven't been looking at the range at an angle point of view. I think I got it already, thanks a lot.
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    Understanding the Parametric Equation for a Sphere

    Erm... not that, I am trying to define a Sphere using VRML a 3D programming language. My teacher gave us this, its derive from the equation of a Sphere : parameters [0.0001 6.282 0.0001 3.141] definition " x=cos(u)*cos(v); y=cos(u)*sin(v); z=sin(u);" Parameter actually just means u's range is...
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    Understanding the Parametric Equation for a Sphere

    I used the formula for a Sphere and I got only half a Sphere : x=cos(u)*cos(v); y=sin(u)*cos(v); z=sin(v); Basically u = 0.0001 to 6.282 and v = 0.0001 to 3.141, its a piece of programming code but the logic is the same. Erm..., did I do anything wrong?
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    Understanding the Parametric Equation for a Sphere

    Putting it in the layman terms does it mean : x = r cos(u) y = r sin(u) 0 <= u <= 2 pi This is to draw the circle, a ratio of a circle is 2 pi. x = r cos(u)cos(v) y = r sin(u)cos(v) z = r sin(v) 0 <= u <= 2 pi 0 <= v <= pi The extra stuff is to make the circle "pop up" till...
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    Understanding the Parametric Equation for a Sphere

    The equation for a circle is x = r cos(u) y = r sin(u) Where u is 0 <= u <= 2 pi, because 2 pi is for calculating circle. While a sphere is x = r cos(u)cos(v) y = r sin(v)cos(v) z = r sin(v) Where u is the same, 2 pi but v is 0<= v <= 1 pi. Why only 1 pi for v? and not 2...
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    How do you differentiate logarithms with different bases and exponents?

    Its 2^{n/2} And oops my bad, I meant how do I differentiate lg^2 x n where lg is log base 2. Since lg is log base 2 and its to the power of 2 wouldn't it be be 1? and if we differentiate n its 1?
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    How do you differentiate logarithms with different bases and exponents?

    How do you differentiate : 2^n/2? You can't you just use the power rule? The correct answer is 2^n/2 (In^2) 1/2 lg^2 x n Where lg is log base 2. The correct answer is 2lgn 1/n^2 . 1/n Why is this so? Isn't lg^2 = 1? And differentiate n and we get 1? Sorry if I sound...
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    Need clarification on Limits/Big-Oh/Big Omega/Big Theta

    About Big-Oh/Big Omega/Big Theta : Limit of n approching inifinity f(n)/g(n) = c < inifinity means its Big-Oh Limit of n approching inifinity f(n)/g(n) = c > 0 means its Big-Omega Limit of n approching inifinity f(n)/g(n) = 0 < c < inifinity means its Theta Does that mean that they are...
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    Need clarification on Limits/Big-Oh/Big Omega/Big Theta

    Ah I see. Therefore, is it safe to say for simple functions like (4n + 3)/n I can just sub in a few number to determine where the limit is leaning towards and therefore get the limit. But for really large number like n/(e to the power of n), where its hard or I can't sub in any numbers and...
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    Need clarification on Limits/Big-Oh/Big Omega/Big Theta

    Oops my bad, my bad. What I meant was (4n + 3)/n, not 4n + 3/n. Is both f(n) and g(n) reaching infinity now? But no L Hospital was used in the example though.
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    Need clarification on Limits/Big-Oh/Big Omega/Big Theta

    Y is n reaching 0? Isn't n reaching infinity?
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    Need clarification on Limits/Big-Oh/Big Omega/Big Theta

    I know that they are near infinity but I can't tell why? Like the previous example 4n + 3/n, aren't both f(g) and f(n) near infinity too?
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    Need clarification on Limits/Big-Oh/Big Omega/Big Theta

    Limit of n approching inifinity 4n / e^n = 0 (L Hospital Rule used) Y is the L Hospital Rule needed here then?
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