1494a50123
* fix: restructure certifications guide articles * fix: added 3 dashes line before prob expl * fix: added 3 dashes line before hints * fix: added 3 dashes line before solutions
36 lines
1.1 KiB
Markdown
36 lines
1.1 KiB
Markdown
---
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title: Sum square difference
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---
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# Problem 6: Sum square difference
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---
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## Problem Explanation
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- Sum of first n natural numbers can be calculated by using this formula:
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- 
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- Sum of squares of n natural numbers can be calculated by using this formula:
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- 
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- We can calculate the values using the above formula and subtract them to get the result.
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---
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## Solutions
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<details><summary>Solution 1 (Click to Show/Hide)</summary>
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```js
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function sumSquareDifference(n) {
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const sumOfN = (n*(n+1))/2;
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const sumOfNSquare = (n*(n+1)*(2*n+1))/6;
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//** is exponentaial operator added in ES7, it's equivalent to Math.pow(num, 2)`
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return (sumOfN ** 2) - sumOfNSquare;
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}
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```
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#### Relevant Links
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- [Sum of n numbers - Wikipedia](https://en.wikipedia.org/wiki/1_%2B_2_%2B_3_%2B_4_%2B_%E2%8B%AF)
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- [Sum of n square numbers - Wikipedia](https://en.wikipedia.org/wiki/Square_pyramidal_number)
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</details> |