Question

2000=n/2[2*3+(n-1)3] solve the problem

Answer 1

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Answer 2

2000=n/2[2*3+(n-1)3]
2000=n/2[6+3n-3]
2000=n/2(3+3n)
4000=n(3+3n)
4000=3n+3n²
3n²+3n-4000=0