47 lines
		
	
	
		
			1009 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			47 lines
		
	
	
		
			1009 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| ---
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| id: 5900f4621000cf542c50ff75
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| title: 'Problem 246: Tangents to an ellipse'
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| challengeType: 5
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| forumTopicId: 301893
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| dashedName: problem-246-tangents-to-an-ellipse
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| ---
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| 
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| # --description--
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| 
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| A definition for an ellipse is:
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| 
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| Given a circle c with centre M and radius r and a point G such that d(G,M)
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| 
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| The construction of the points of the ellipse is shown below.
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| 
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| Given are the points M(-2000,1500) and G(8000,1500). Given is also the circle c with centre M and radius 15000. The locus of the points that are equidistant from G and c form an ellipse e. From a point P outside e the two tangents t1 and t2 to the ellipse are drawn. Let the points where t1 and t2 touch the ellipse be R and S.
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| 
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| For how many lattice points P is angle RPS greater than 45 degrees?
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| 
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| # --hints--
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| 
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| `euler246()` should return 810834388.
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| 
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| ```js
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| assert.strictEqual(euler246(), 810834388);
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| ```
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| 
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| # --seed--
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| 
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| ## --seed-contents--
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| 
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| ```js
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| function euler246() {
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| 
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|   return true;
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| }
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| 
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| euler246();
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| ```
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| 
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| # --solutions--
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| 
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| ```js
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| // solution required
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| ```
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