47 lines
1009 B
Markdown
47 lines
1009 B
Markdown
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---
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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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# --description--
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A definition for an ellipse is:
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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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The construction of the points of the ellipse is shown below.
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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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For how many lattice points P is angle RPS greater than 45 degrees?
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# --hints--
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`euler246()` should return 810834388.
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```js
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assert.strictEqual(euler246(), 810834388);
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```
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# --seed--
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## --seed-contents--
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```js
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function euler246() {
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return true;
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}
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euler246();
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```
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# --solutions--
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```js
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// solution required
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```
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