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Show that 2+5+8+------+(3n-1)=n(3n+1)/2 |
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Answer» Nth term = 3n-1 Now to find sum of n terms Sum = summation tn sum of n natural numbers = n(n+1)/2 Sum=summation tn =3(n(n+1)/2 - n =(3n2+3n-2n)/2 =3n2+n/2 =n(3n+1)/2 hence proved . |
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