document.write( "Question 954448: 1+5+14+30+55........
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Algebra.Com's Answer #582926 by hemu_da(13)\"\" \"About 
You can put this solution on YOUR website!
It is the series of sum of the first \"n%5E2\" terms..\r
\n" ); document.write( "\n" ); document.write( "We know that....\r
\n" ); document.write( "\n" ); document.write( "Sum of first n term is \"n%28n%2B1%29%2F4\"\r
\n" ); document.write( "\n" ); document.write( "Sum of the square of the first n term is \"%28n%28n%2B1%29%282n%2B1%29%29%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "Sum of the cube of the first n numbers is \"%28n%5E2%28n%2B1%29%5E2%29%2F2\"\r
\n" ); document.write( "\n" ); document.write( "Given that..\r
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\n" ); document.write( "\n" ); document.write( "\"1%2B5%2B14%2B30%2B55%2B.........\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28n%28n%2B1%29%282n%2B1%29%29%2F6\".\r
\n" ); document.write( "\n" ); document.write( "We can write this series also as--- sum= \"sum%28%28%28n%28n%2B1%29%282n%2B1%29%29%2F6%29%2Cn=1%2Cn%29\".
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\n" ); document.write( "\n" ); document.write( "Sum=\"sum%28%28%28%28n%5E2%2Bn%29%282n%2B1%29%29%2F6%29%2Cn=1%2Cn%29\"
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\n" ); document.write( "\n" ); document.write( "Sum=\"sum%28%28%282n%5E3%2B3n%5E3%2Bn%29%2F6%29%2Cn=1%2Cn%29\"
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\n" ); document.write( "\n" ); document.write( "Sum=\"sum%28%28%28%28n%5E3%29%2F3%29%2B%28%28n%5E2%29%2F2%29%2B%28n%2F6%29%29%2Cn=1%2Cn%29\"
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\n" ); document.write( "\n" ); document.write( "Sum=
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\n" ); document.write( "\n" ); document.write( "Sum= \r
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\n" ); document.write( "Sum= \"%28n%28n%2B1%29%28n%28n%2B1%29%2B%282n%2B1%29%2B1%29%29%2F12\"\r
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\n" ); document.write( "Sum= \"%28n%28n%2B1%29%28n%5E2%2B3n%2B2%29%29%2F12\"\r
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\n" ); document.write( "\n" ); document.write( "Sum= \"%28n%28n%2B1%29%28n%2B1%29%28n%2B2%29%29%2F12\"\r
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\n" ); document.write( "Sum= \"%28n%28n%2B1%29%5E2%28n%2B2%29%29%2F12\".... Ans..\r
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\n" ); document.write( "To varify this formula lets take n=4...
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\n" ); document.write( "Sum=\"%284%284%2B1%29%5E2%284%2B2%29%29%2F12\"
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\n" ); document.write( "Sum=\"%284%2A25%2A6%29%2F12\"
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\n" ); document.write( "Sum= 50.
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\n" ); document.write( "In the series... Sum of first 4 terms= 1+5+14+30 = 50..
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\n" ); document.write( "Which is equal to the our calculated Ans....
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