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The kth term, t(k) is given by t(k) = 2k2 + 2k
So the sum of the first n terms is 2*(12+22+32+...+n2) + 2*(1+2+3+...+n)
= 2*n(n+1)(2n+1)/6 + 2*n(n+1)/2
= n(n+1)*(2n+1)/3 + n(n+1)
= n(n+1)*(2n+1+3)/3
= 2*n(n+1)(n+2)/3
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What is the sum of the first 11 terms of the arithmetic series in which a1 -12 and d 5?
Sum = n/2(2a + (n-1)d) = 11/2 x (2 x -12 + 10 x 5) = 11/2 x 26 = 143
What is the fraction that is in the lowest terms and the sum of the terms is nineteen?
7/12 is another.
What is the sum of 36 divided by 39?
0.9231
What is average of 10 6 12?
Calculating an average is done in two steps: - First: you calculate the sum of the terms whose average you would like to calculate. - Second: you divide the sum of the terms by their number. In your case: - First: 10 + 6 + 12 = 28 - Second: 28 / 3 = 9.33333.... 3 is the number of terms added together which are: 10, 6 and 12 (3 numbers). Answer: Therefore your average is: 9.33333....
What is the sum of 21 and 12?
The sum of 21 and 12 is 33.
Find the sum of the first 48 terms of an aritmetic sequance 2 4 6 8?
Sum of 1st 2 terms, A2 = 2 + 4 = 6 Sum of 1st 3 terms, A3 = 2 + 4 + 6 = 12 Sum of 1st 4 terms A4 = 2 + 4 + 6 + 12 = 20 you can create a formula for the sum of the 1st n terms of this sequence Sum of 1st n terms of this sequence = n2 + n so the sum of the first 48 terms of the sequence is 482 + 48 = 2352
What is the sum of the first 11 terms of the arithmetic series in which a1 -12 and d 5?
Sum = n/2(2a + (n-1)d) = 11/2 x (2 x -12 + 10 x 5) = 11/2 x 26 = 143
How do factor the sum of terms as a product of the greatest common factor and the sum of 72 and 60?
12(6 + 5)
What is the fraction that is in the lowest terms and the sum of the terms is nineteen?
7/12 is another.
What two terms when multiplied gives a product of -12 and sum of 13?
-0.86546 and 13.86546 (approx).
What is the sum of 36 divided by 39?
0.9231
What is the sum of the first 12 terms of the arithmetic sequence?
The sum of the first 12 terms of an arithmetic sequence is: sum = (n/2)(2a + (n - 1)d) = (12/2)(2a + (12 - 1)d) = 6(2a + 11d) = 12a + 66d where a is the first term and d is the common difference.
How many terms of the ap 43 39 35 ... be taken so that their sum is 252?
12 terms. Sum_of_ap = n(2a + (n-1)d) ÷ 2 For 43, 39, 35, ... a = 43, d = -4 ⇒ 252 = n(2 x 43 + (n - 1) x -4) ÷ 2 ⇒ 252 = 45n -2n2 ⇒ 2n2 - 45n + 252 = 0 ⇒ (2n - 21)(n - 12) = 0 ⇒ n = 101/2 or 12 101/2th terms do not make sense, so cannot be an answer. Thus 12 terms are needed. What happens is that the sum increases whilst the terms are positive. After 10 terms, the sum is still less than 252. The 11th term is the last positive term and takes the sum over 252; the 12th term is the first negative term and takes the sum back down to 252.
who find the sum of the first 12 terms of the sequence described by the formula:U n = 3n – 8?
i need it nowww
If the sum of an infinite geometric series is 12 and the common ratio is one third then term 1 is what?
Eight. (8)
What is average of 10 6 12?
Calculating an average is done in two steps: - First: you calculate the sum of the terms whose average you would like to calculate. - Second: you divide the sum of the terms by their number. In your case: - First: 10 + 6 + 12 = 28 - Second: 28 / 3 = 9.33333.... 3 is the number of terms added together which are: 10, 6 and 12 (3 numbers). Answer: Therefore your average is: 9.33333....
What is the sum of the geometric sequence 4 12 36 if there are 9 terms?
Un = 4*3n-1 S9 = 39364
