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How do you find the expression for the nth term in an exponential sequence.

Example:-
1, 3, 7, 15

User Rusheb
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2 Answers

3 votes

Final answer:

To find the nth term expression for the given sequence, observe the pattern that each term is one less than a power of 2. Thus the nth term of the sequence 1, 3, 7, 15 is given by the formula
T(n) = 2^n - 1.

Step-by-step explanation:

To find the expression for the nth term in an exponential sequence like 1, 3, 7, 15, we first need to understand that this does not seem to be a typical exponential sequence where each term is obtained by multiplying a fixed number with the previous term. Instead, this sequence follows a pattern where each term is one less than a power of 2 (i.e., an exponential sequence with base 2). For example,
1 is 2^1 - 1, 3 is 2^2 - 1, 7 is 2^3 - 1, and so on. Thus, to find the nth term, the pattern implies that the nth term is 2^n - 1.

This can be verified by listing the terms and seeing if they match the given sequence. We have:

  • 1st term:
    2^1 - 1 = 1
  • 2nd term:
    2^2 - 1 = 3
  • 3rd term:
    2^3- 1 = 7
  • 4th term:
    2^4 - 1 = 15

Hence, the nth term for this specific sequence can be written as T(n) =
2^n - 1.

User Purecharger
by
7.2k points
5 votes

Answer:

Step-by-step explanation:


Ans:n^th=2n-1

we are going to use the formula of arithmetic sequence.

We need to find the first term of the sequence which is 1 and find the difference between any two number.

Then simply multiply the different by (n-1)

Finally add the result with first term which is 1.

User Lentinant
by
7.5k points