Saliya's Blogs

Mostly technical stuff with some interesting moments of life

How to Compute The Sum of Squares for First N Integers

Saliya Ekanayake 9:49 PM , , No comments
We need to find,
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answer 
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How to get that?
Let’s consider the expansion of clip_image002[9]
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Therefore,
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Now let’s substitute values for clip_image002[15]
clip_image002[21]
when
 clip_image002[17]
clip_image002[23]
when
 clip_image002[25]
…
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when
 clip_image002[29]
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when
 clip_image002[33]
if you sum them from top to bottom
clip_image002[35]
Taking the sum of arithmetic series,
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Therefore,
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clip_image002[43]
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Special thanks to my friend Jayampathi Rathnayake (http://www.math.indiana.edu/people/profile.phtml?id=jratnaya) for his insight on the approach.

Another good resource http://www.trans4mind.com/personal_development/mathematics/series/sumNaturalSquares.htm

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