Answer:
Step-by-step explanation:
Use the identity for the sum of squares of n natural numbers:
Since we have the sum, 56980:
- n(n + 1)(2n + 1)/6 = 56980
- (n² + n)(2n + 1) = 56980*6
- 2n³ + 3n² + n - 341880 = 0
Solve the equation graphically to get a natural solution of n = 55
