62 lines
870 B
Markdown
62 lines
870 B
Markdown
---
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id: 5900f3721000cf542c50fe85
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title: 问题6：求和方差
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challengeType: 5
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videoUrl: ''
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---
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# --description--
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前十个自然数的平方和是，
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1
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<sup>2</sup>
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- 2
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<sup>2</sup>
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- ... + 10
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<sup>2</sup>
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= 385
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前十个自然数之和的平方是，
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（1 + 2 + ... + 10）
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<sup>2</sup>
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= 55
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<sup>2</sup>
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= 3025
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因此，前十个自然数的平方和与和的平方之间的差值为3025 - 385 = 2640.求出前`n`自然数的平方和与总和的平方之间的差值。
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# --hints--
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`sumSquareDifference(10)`应该返回2640。
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```js
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assert.strictEqual(sumSquareDifference(10), 2640);
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```
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`sumSquareDifference(20)`应该返回41230。
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```js
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assert.strictEqual(sumSquareDifference(20), 41230);
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```
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`sumSquareDifference(100)`应该返回25164150。
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```js
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assert.strictEqual(sumSquareDifference(100), 25164150);
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```
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# --solutions--
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