Find the value of the sum of k^2 for k = 1 to 5.
Answer and explanation
Correct answer: B. 55
- Step 1: Use the formula sum k^2 = n(n + 1)(2n + 1)/6. Step 2. = 5 x 6 x 11 / 6 = 55. Answer: 55. Why not the others: 15: That is the sum of the first 5 integers, not of their squares. 225: That is the sum of cubes. 25: That is n squared, which is the sum of odd numbers.
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