41 lines
964 B
Markdown
41 lines
964 B
Markdown
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---
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id: 5900f3f61000cf542c50ff09
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title: 'Problem 138: Special isosceles triangles'
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challengeType: 5
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forumTopicId: 301766
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dashedName: problem-138-special-isosceles-triangles
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---
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# --description--
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Consider the isosceles triangle with base length, b = 16, and legs, L = 17.
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By using the Pythagorean theorem it can be seen that the height of the triangle, h = √(172 − 82) = 15, which is one less than the base length. With b = 272 and L = 305, we get h = 273, which is one more than the base length, and this is the second smallest isosceles triangle with the property that h = b ± 1. Find ∑ L for the twelve smallest isosceles triangles for which h = b ± 1 and b, L are positive integers.
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# --hints--
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`euler138()` should return 1118049290473932.
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```js
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assert.strictEqual(euler138(), 1118049290473932);
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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 euler138() {
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return true;
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}
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euler138();
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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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