document.write( "Question 984370: Find the sum of the first n terms of the following series
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Algebra.Com's Answer #605221 by Edwin McCravy(20065)\"\" \"About 
You can put this solution on YOUR website!

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document.write( "\"%22%22=%22%22\"\"%22%22=%22%22\"\"sum%28%28k%5E3%2B3k%5E2%2B2k%29%2Ck=1%2Cmatrix%281%2C3%2C%22%22%2C%22%22%2Cn%29%29\"\"%22%22=%22%22\"\"sum%28%28k%5E3%29%2Ck=1%2Cmatrix%281%2C3%2C%22%22%2C%22%22%2Cn%29%29\"\"%22%22%2B%22%22\"\"sum%28%283k%5E2%29%2Ck=1%2Cmatrix%281%2C3%2C%22%22%2C%22%22%2Cn%29%29\"\"%22%22%2B%22%22\"\"sum%28%282k%5E%22%22%29%2Ck=1%2Cmatrix%281%2C3%2C%22%22%2C%22%22%2Cn%29%29\"\"%22%22=%22%22\"\r\n" );
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document.write( "\"sum%28%28k%5E3%29%2Ck=1%2Cmatrix%281%2C3%2C%22%22%2C%22%22%2Cn%29%29\"\"%22%22%2B%22%22\"\"3%2Asum%28%28k%5E2%29%2Ck=1%2Cmatrix%281%2C3%2C%22%22%2C%22%22%2Cn%29%29\"\"%22%22%2B%22%22\"\"2%2Asum%28%28k%5E%22%22%29%2Ck=1%2Cmatrix%281%2C3%2C%22%22%2C%22%22%2Cn%29%29\"\"%22%22=%22%22\"\"%28n%5E2%28n%2B1%29%5E2%29%2F4%29\"\"%22%22%2B%22%22\"\"3%28%28n%28n%2B1%29%282n%2B1%29%29%2F6%29\"\"%22%22%2B%22%22\"\"2%28n%28n%2B1%29%2F2%29\"\"%22%22=%22%22\"\r\n" );
document.write( "\"%28n%5E2%28n%2B1%29%5E2%29%2F4%29\"\"%22%22%2B%22%22\"\"%28n%28n%2B1%29%282n%2B1%29%29%2F2\"\"%22%22%2B%22%22\"\"2n%28n%2B1%29%2F2\"\"%22%22=%22%22\"\"%28n%5E2%28n%2B1%29%5E2%29%2F4%29\"\"%22%22%2B%22%22\"\"%282n%28n%2B1%29%282n%2B1%29%29%2F4\"\"%22%22%2B%22%22\"\"4n%28n%2B1%29%2F4\"\"%22%22=%22%22\"\"%28n%5E2%28n%2B1%29%5E2%2B2n%28n%2B1%29%282n%2B1%29%2B4n%28n%2B1%29%29%2F4\"\"%22%22=%22%22\"\r\n" );
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document.write( "Factor out n(n+1) on top:\r\n" );
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document.write( "\"%22%22=%22%22\"\"%28n%28n%2B1%29%28n%5E2%2Bn%2B4n%2B2%2B4++%29++%29%2F4\"\"%22%22=%22%22\"\"%28n%28n%2B1%29%28n%5E2%2B5n%2B6++%29++%29%2F4\"\"%22%22=%22%22\"\"%28n%28n%2B1%29%28n%2B2%29%28n%2B3%29%29%2F4\"\r\n" );
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document.write( "Edwin
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