45 lines
685 B
Markdown
45 lines
685 B
Markdown
---
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id: 5900f4571000cf542c50ff6a
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title: 'Problem 235: An Arithmetic Geometric sequence'
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challengeType: 5
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forumTopicId: 301879
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dashedName: problem-235-an-arithmetic-geometric-sequence
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---
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# --description--
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Given is the arithmetic-geometric sequence u(k) = (900-3k)rk-1.
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Let s(n) = Σk=1...nu(k).
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Find the value of r for which s(5000) = -600,000,000,000.
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Give your answer rounded to 12 places behind the decimal point.
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# --hints--
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`euler235()` should return 1.002322108633.
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```js
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assert.strictEqual(euler235(), 1.002322108633);
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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 euler235() {
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return true;
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}
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euler235();
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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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