n² + 2ⁿ

70

Find the sum of the following series upto n terms 3 × 8 + 6 × 11 + 9 × 14+….

71

1²+ (1² + 2²) + (1² + 2² + 3²) + ……

72

Find the sum to μ terms of the series in Exercise 8 to 10 whose nth terms is given by n(n+1)(n + 4)

74

Find the sum to n terms of the following series whose nth term is given by (2n – 1)².