Can anyone solve the first question !

  255

Step-by-step explanation:

The recursive formula is used to find the terms one-by-one, unless you convert it to an explicit formula.

  first term (given): 3

  2nd term = 4·3 +3 = 15

  3rd term = 4·15 +3 = 63

  4th term = 4·63 +3 = 255

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Looking at the sequence of terms, we see that an explicit formula might be ...

  an = 4^n -1

Then the 4th term is

  a4 = 4^4 -1 = 256 -1 = 255

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Comment on the problem statement

This is NOT an Arithmetic Progression. An arithmetic progression has a common difference between terms. Here, the differences are 12, 48, 192, numbers that are different from one pair of adjacent terms to the next.

17

step-by-step explanation: