Difference between revisions of "User:5849206328x"

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//real f(real x) { return 3 * (-1/x + 1/(2*x^2)); }
 
//real f(real x) { return 3 * (-1/x + 1/(2*x^2)); }
//pair g(real t, real k) { return (1/k * 3/5 * (1 - e^(-k * t)), -t/k + 1/k * (4/5 + 1/k) * (1 - e^(-k * t))); }
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pair g(real t) { return 16/(1 + 5/3 * cos(pi * t/180)) * dir(t); }
  
//draw(graph(f,0.0001,5));
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draw(graph(g,-105,105));
  
pair A = (7, 4 * sqrt(141)/5);
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pair A = (4, 8 * sqrt(10)/3);
  
draw(ellipse((-15,0),25,20)); draw((-50,0)--(20,0)); draw((-15,-25)--(-15,25)); draw((0,0)--(0,16),dashed);
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draw((-25,0)--(25,0)); draw((15,-25)--(15,25)); draw((0,0)--(0,16),dashed);
dot((0,0)); draw((0,0)--A--(A + (-3,4.1)),EndArrow); dot(A);  
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dot((0,0)); draw((0,0)--A--(A + (-1.7,4.1)),EndArrow); dot(A);
 +
draw((-15,-40)--(30,20),dashed); draw((-15,40)--(30,-20),dashed);
  
label("$O$",(0,0),S); label("$ea$",(-8,0),S); label("$a$",(-28,0),S); label("$b$",(-15,10),W); label("$l$",(0,8),W);
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//label("$O$",(0,0),S); label("$ea$",(-8,0),S); label("$a$",(-28,0),S); label("$b$",(-15,10),W); label("$l$",(0,8),W);
label("$\mathbf{r}$",A/2,NW); label("$\theta$",(1,0),NE); label("$m$",A,NE);
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//label("$\mathbf{r}$",A/2,NW); label("$\theta$",(1,0),NE); label("$m$",A,NE);
  
//limits((-1,-2),(5.2,3.2),Crop);
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limits((-25,-25),(25,25),Crop);
  
// e = 3/5, l = 9, a = 25, b = 20
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// e = 5/3, l = 16, a = 9, b = 12
// (x + 15)^2/25^5 + y^2/20^2 = 141 * 400/625 = 141 * 16/25
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// (x - 15)^2/81 - y^2/144 = 1, y^2/144 = 40/81, 40 * 144/81, sqrt(40) * 12/9 = 8sqrt(10)/3
 
</asy>
 
</asy>

Revision as of 21:03, 19 July 2015

[asy] import slopefield;  //size(288);  real e  = 2.718281828459045235360287471352662497757247093699959574966967627724076630353; real pi = 3.141592653589793238462643383279502884197169399375105820974944592307816406286;  // Label f; // f.p=fontsize(6); //xaxis(0,5); //yaxis(-2,3);  //real f(real x) { return 3 * (-1/x + 1/(2*x^2)); } pair g(real t) { return 16/(1 + 5/3 * cos(pi * t/180)) * dir(t); }  draw(graph(g,-105,105));  pair A = (4, 8 * sqrt(10)/3);  draw((-25,0)--(25,0)); draw((15,-25)--(15,25)); draw((0,0)--(0,16),dashed); dot((0,0)); draw((0,0)--A--(A + (-1.7,4.1)),EndArrow); dot(A); draw((-15,-40)--(30,20),dashed); draw((-15,40)--(30,-20),dashed);  //label("$O$",(0,0),S); label("$ea$",(-8,0),S); label("$a$",(-28,0),S); label("$b$",(-15,10),W); label("$l$",(0,8),W); //label("$\mathbf{r}$",A/2,NW); label("$\theta$",(1,0),NE); label("$m$",A,NE);  limits((-25,-25),(25,25),Crop);  // e = 5/3, l = 16, a = 9, b = 12 // (x - 15)^2/81 - y^2/144 = 1, y^2/144 = 40/81, 40 * 144/81, sqrt(40) * 12/9 = 8sqrt(10)/3 [/asy]