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NEST2021MathematicsSequences and Series

Let a_n n N and b_n n N be two sets of real numbers, where N denotes the set of natural numbers. Define s_k= _ i=1 ^k a_i and t_k= _ i=1 ^k b_i . Then _ i=1 ^k a_i b_i is equal to

Options

  1. A_ i=1 ^ k-1 s_i (b_i-b_ i+1 )+s_k b_k
  2. B_ i=1 ^ k-1 t_i (a_i+a_ i+1 )+t_k a_k
  3. C_ i=2 ^k s_i (b_i-b_ i-1 )+s₁ b₁
  4. D_ i=2 ^k t_i (a_i-a_ i-1 )+t₁ a₁

Correct answer

A. _ i=1 ^ k-1 s_i (b_i-b_ i+1 )+s_k b_k

Step-by-step solution

No solution available.

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