Question

Tolong bantu cara cepat nomor 12 trimakasih

Answer 1

Deretnya:
3, 5, 7, ... , 401
a = 3
b = 5 - 3 = 2
Un = 401
Un = a + (n - 1)b
401 = 3 + 2n - 2
n = 200
S200 = (200/2)(2(3) + 199(2))
= 100(6 + 398)
= 40400