Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

Write an explicit formula for 
a_(n), the 
n^("th ") term of the sequence 
27,-9,3,dots
Answer: 
a_(n)=

Write an explicit formula for an a_{n} , the nth  n^{\text {th }} term of the sequence 27,9,3, 27,-9,3, \ldots \newlineAnswer: an= a_{n}=

Full solution

Q. Write an explicit formula for an a_{n} , the nth  n^{\text {th }} term of the sequence 27,9,3, 27,-9,3, \ldots \newlineAnswer: an= a_{n}=
  1. Identify pattern in sequence: We first identify the pattern in the sequence. The sequence starts with 2727 and each term is divided by 3-3 to get the next term: 27,9,3,27, -9, 3, \ldots
  2. Calculate ratio: This is a geometric sequence because each term is obtained by multiplying the previous term by a constant ratio. To find the ratio rr, we divide the second term by the first term: r=(9)/27=13r = (-9) / 27 = -\frac{1}{3}.
  3. Use geometric sequence formula: The first term of the sequence, a1a_1, is 2727. The nnth term of a geometric sequence is given by the formula an=a1×r(n1)a_n = a_1 \times r^{(n-1)}, where a1a_1 is the first term and rr is the common ratio.
  4. Substitute values into formula: Substituting the values of a1a_1 and rr into the formula, we get an=27×(13)(n1)a_n = 27 \times (-\frac{1}{3})^{(n-1)}.
  5. Simplify if necessary: This is the explicit formula for the nnth term of the sequence. It can be simplified further if necessary, but in this case, it is already in its simplest form.

More problems from Convert between explicit and recursive formulas