Which sequence has the given subscript notation a1=6

; an=an−1+2
when defined recursively?(1 point)
Responses

an=8,10,12,14,16, . . .
a subscript n baseline equals 8 comma 10 comma 12 comma 14 comma 16 comma dot dot dot

an=6,4,2,0,−2, . . .
a subscript n baseline equals 6 comma 4 comma 2 comma 0 comma negative 2 comma dot dot dot

an=4+2n
a subscript n baseline equals 4 plus 2 n

an=6+2n
a subscript n baseline equals 6 plus 2 n
Remaining Attempts : 3
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1 answer

The sequence defined recursively by \( a_1 = 6 \) and \( a_n = a_{n-1} + 2 \) describes a sequence where each term is 2 more than the previous term, starting from 6.

Let's compute the first few terms:

  • \( a_1 = 6 \)
  • \( a_2 = a_1 + 2 = 6 + 2 = 8 \)
  • \( a_3 = a_2 + 2 = 8 + 2 = 10 \)
  • \( a_4 = a_3 + 2 = 10 + 2 = 12 \)
  • \( a_5 = a_4 + 2 = 12 + 2 = 14 \)
  • \( a_6 = a_5 + 2 = 14 + 2 = 16 \)

This gives us the sequence: \( 6, 8, 10, 12, 14, 16, \ldots \)

Now, let's analyze the provided options:

  1. \( a_n = 8, 10, 12, 14, 16, \ldots \) - This does not start at 6.
  2. \( a_n = 6, 4, 2, 0, -2, \ldots \) - This sequence decreases, so it does not match.
  3. \( a_n = 4 + 2n \) - If \( n = 1 \), then \( a_1 = 4 + 2(1) = 6 \), but this doesn’t match the pattern of the generated sequence from the recursion.
  4. \( a_n = 6 + 2n \) - For \( n = 1 \), \( a_1 = 6 + 2(1) = 8 \), but it becomes \( 6 + 2(2) = 10 \), etc. So this does not match when \( n = 1 \).

None of the fourth choices accurately represent the generated sequence.

The correct form for the sequence given by the recursive definition is \( a_n = 6 + 2(n - 1) = 2n + 4 \), which matches the recursive description.

Based on available responses, the one that is most similar considering the base term will be option 4 with \( a_n = 6 + 2n \) (considering that if you start at n=0, then the first term aligns).

However, specifically, it would be \( a_n = 6, 8, 10, 12, 14, 16, \ldots \) which is formatted incorrectly in the available choices.

If only that sequence were presented, it would be the correct response.