Find the value of the sum of k^2 for k = 1 to 12.
Answer and explanation
Correct answer: C. 650
- Step 1: Use the formula sum k^2 = n(n + 1)(2n + 1)/6. Step 2. = 12 x 13 x 25 / 6 = 650. Answer: 650. Why not the others: 78: That is the sum of the first 12 integers, not of their squares. 6084: That is the sum of cubes. 144: That is n squared, which is the sum of odd numbers.
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