Question

find the sum of the series 2 cube minus 1 + 4 cube minus 3 Cube + 6 cube minus 15 cube to n terms ​

Answer 1

Answer:

2³- 1 + 4³ - 3³ + 6³ - 5³ = (8-1) + (64 - 27) + (216 - 125)

8th term = 7³ = 343

nth term = nth term = (n*2)³ if n is at odd place

(n*2 - 1)³ if n is at even place