Enter a recursive rule for the geometric sequence. 3, −12, 48, −192, 

  a[1] = 3; a[n] = -4a[n-1]

Step-by-step explanation:

The first term is 3, so that is the first part of the recursive rule: a[1] = 3.

Each term is -4 times the previous term, so that is the second part of the recursive rule: a[n] = -4a[n-1].

You know a geometric sequence has a common ratio. That ratio can be found by dividing any term by the one before: -12/3 = -4. This is the value that each term is multiplied by to get the next term.

y = 2x

step-by-step explanation:

if you divide each number in the sequence, you'll see that they all have a multiple factor of 2. each number in the series, and any other numbers which may continue, will be multiplied by 2. therefore, y is the next number in the sequence, and x is the current one, so, our formula will be y = 2x.