Recent content by ParoXsitiC

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    Discrete Math, Intro Proof

    One person said it's OK. Another said it's not. And one just gave just a general definition. If I cannot assume -R(a) is true then I need a push in the right direction on how to solve this without using this assumption, or at least a hint on how I can proof -R(a) is true using rules.
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    Discrete Math, Intro Proof

    Homework Statement Using the rules of inference, prove that if ∀x(P(x) ∨ Q(x)) and ∀x((¬P(x) ∧ Q(x)) → R(x)) are true, then ∀x(¬R(x) → P(x)) is true as well. Homework Equations The Attempt at a Solution The problem arises step 5. I feel this is correct but the...
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    Sphere with a hole drilled in center

    Nevermind, when evaulating both possible ways using b = 0 (just getting volume of a sphere no drill) I get 4/3 Pi R^2 when z goes from +- sqrt(R^2 - r^2) - which is the volumne of a sphere. So obviously that one is right, it makes sense visually but I know in some cases you must use the...
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    Sphere with a hole drilled in center

    Homework Statement Find volume of a sphere with radius R with a hole drilled through the center of radius b. (b<R) Homework Equations cos thera = adj / hyp The Attempt at a Solution 4\,\int _{0}^{\arccos \left( {\frac {b}{R}} \right) }\!\int _{0}^{\pi }\!\int...
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    Finding intersection of line and circle.

    \left( -\sqrt {2}+t \right) ^{2}+ \left( \sqrt {2}+t \right) ^{2}=25 \, \left( \cos \left( t \right) \right) ^{2}+25\, \left( \sin \left( t \right) \right) ^{2} \left( -\sqrt {2}+t \right) ^{2}+ \left( \sqrt {2}+t \right) ^{2}=25( \, \left( \cos \left( t \right) \right) ^{2}+\left(...
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    Finding intersection of line and circle.

    http://www.wolframalpha.com/input/?i=%28-sqrt%282%29%2Bt%29%5E2+%2B+%28sqrt%282%29%2Bt%29%5E2+%3D+%285+*+cos%28t%29%29%5E2+%2B+%285+*+sin%28t%29%29%5E2 Gives me t= ± sqrt(21/2) Pluggin this into X= 5*cos(t), gives ~ -4.97 Of which according to maple the approx points of X I am...
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    Finding intersection of line and circle.

    How it relates to any mathematical formula or understanding, taking your reply literally : (-sqrt(2)+t)^2 + (sqrt(2)+t)^2 = (5 * cos(t))^2 + (5 * sin(t))^2 Yielded nothing useful.
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    Finding intersection of line and circle.

    Homework Statement I have a line obtained from using a slope of 1 and point (-sqrt(2),sqrt(2)): y - sqrt(2) = 1 (x+sqrt(2)) y = 2*sqrt(2) + x and a circle with radius 5 centered at origin. My thought was to solve this parametrically The line is the tangent line (blue...
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    Vectors, Planes, and intersections

    x+2y+5z=1- should be x+2y+5z=10 Also I had make sure scaling was constrained, but now trying to do it in maple it looks right. so must of been a small mistake. None the less taking your advice I got t = 100/69 solving for xyz: x = 62/69 y = 64/69 z = 100/69 And it checks for all 3 planes...
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    Vectors, Planes, and intersections

    Homework Statement The planes 3x+2y+z=6 and x+2y+5z=1- intersect along the line (x+2)/2 = (y-6)/(-7/2)= z. A third plane passes through the origin and is perpendicular to the intersection of the first two planes, at what point do the three planes intersect? Homework Equations...
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    Equation of plane given points

    That is how it is worded, reading it word for word. I thought it was weird too given 6 points instead of the common 3
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    Equation of plane given points

    I forgot to update the formula with -14: -2x-6y-14z = -78 Still when using (10,2,2) I get -60 and not -78
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    Equation of plane given points

    Okay I had 14 when should be -14 PQ x PR = <-2,-6,-14> Plug in point P into formula and get: -2x-6y+14z = -78 Now point Q works out to be -78 but the point (10,2,2) turns out to be -60 Is this a trick question?
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    Equation of plane given points

    Homework Statement Find equation of plane containing points: (1,1,5),(3,5,3),(8,8,1),(10,2,2),(18,6,-1),(-1,-3,6) Homework Equations Find 2 vectors given 3 points, using a common point. The cross product of these 2 vectors will be the normal vector of the plane. Use normal vector...
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