0
To find the nth term of an arithmetic sequence, you need to first identify the common difference between consecutive terms. In this case, the common difference is -2 (subtract 2 from each term to get the next term). The formula to find the nth term of an arithmetic sequence is: a_n = a_1 + (n-1)d, where a_n is the nth term, a_1 is the first term, n is the term number, and d is the common difference. Plugging in the values from the sequence (a_1=7, d=-2), the nth term formula becomes: a_n = 7 + (n-1)(-2) = 9 - 2n.
Still curious? Ask our experts.
Chat with our AI personalities
Steve
Professor
Coach
Add your answer:
Earn +20 pts
How do you find the given term in a geometric sequence?
nth term Tn = arn-1 a = first term r = common factor
This is Q of sequence series hlp me1 2 4 8 16 ..find nth term of the series find sum of first n term?
If you remember taking sequences, you'll recall that there are three main types: 1)Arithmetic Sequence 2)Geometric Sequence 3)Varied-formula Sequence If the difference between the terms is additional or subractional then its an arithmetic sequence, lets check if this is the case, subtract the first term from the second and the second from the third etc : 1, 2, 4, 8, 16 2-1=1 4-2=2 8-4=4....all the answers are not constant so it is not an arithmetic sequence In a geometric sequence, the difference is in multiplication or division so we divide like this t2/t1 then t3/t2 and then t4/t3 and so on: 2/1=2 4/2=2 8/4=2...all the numbers are constant so this sequence we have here is a geometric sequence to find the nth term we use a formula it varies from the kind of sequence you are using, the formula for a geometric sequence is: tn=t1*r^(n-1) The formula might look confusing so ill write it down for you: "term n= term 1 multiplied by common ratio to the power n-1" The 'common ratio' is the constant so in this case it equals 2. tn=1*2^(n-l) that is the farthest you can go, if the question gives you the nth term then you may substitute it yourself. You didn't make yourself very clear with the last part of your question...
How do you find the nth term in a sequence?
Finding the nth term is much simpler than it seems. For example, say you had the sequence: 1,4,7,10,13,16 Sequence 1 First we find the difference between the numbers. 1 (3) 4 (3) 7 (3) 10 (3) 13 (3) 16 The difference is the same: 3. So the start of are formula will be 3n. If it was 3n, the sequence would be 3,6,9,12,15,18 Sequence 2 But this is not our sequence. Notice that each number on sequence 2 is 2 more than sequence 1. this means are final formula will be: 3n+1 Test it out, it works!
Find the quadratic sequences nth term for these 4 sequences which are separated by the letter i iii 7 10 15 22 21 42 iii 2 9 18 29 42 57 iii 4 15 32 55 85 119 iii 5 12 27 50 81 120?
Check if the given sequences are quadratic sequences. 7 10 15 22 21 42 The first difference: 3 5 7 1 21. The second difference: 2 2 6 20. Since the second difference is not constant, then the given sequence is not a quadratic sequence. 2 9 18 29 42 57 The first difference: 7, 9, 11, 13, 15. The second difference: 2 2 2 2. Since the second difference is constant, then the given sequence is a quadratic sequence. Therefore, contains a n2 term. Let n = 1, 2, 3, 4, 5, 6, ... Now, let's refer the n2 terms as, 1, 4, 9, 16, 25, 36. As you see, the terms of the given sequence and n2 terms differ by 1, 5, 9, 13, 17, 21 which is an arithmetic sequence,say {an} with a common difference d = 4 and the first term a = 1. Thus, the nth term formula for this arithmetic sequence is an = a + (n - 1)d = 1 + 4(n - 1) = 4n - 3. Therefore, we can find any nth term of the given sequence by using the formula, nth term = n2 + 4n - 3 (check, for n = 1, 2, 3, 4, 5, 6, ... and you'll obtain the given sequence) 4 15 32 55 85 119 The first difference: 11, 17, 23, 30, 34. The second difference: 6 6 7 4. Since the second difference is not constant, then the given sequence is not a quadratic sequence. 5 12 27 50 81 120 The first difference: 7, 15, 23, 31, 39. The second difference: 8 8 8 8. Since the second difference is constant, then the given sequence is a quadratic sequence. I tried to refer the square terms of sequences such as n2, 2n2, 3n2, but they didn't work, because when I subtracted their terms from the terms of the original sequence I couldn't find a common difference among the terms of those resulted sequences. But, 4n2 works. Let n = 1, 2, 3, 4, 5, 6, ... Now, let's refer the 4n2 terms as, 4, 16, 36, 64, 100, 144. As you see, the terms of the given sequence and 4n2 terms differ by 1, -4, -9, -14, -19, -24 which is an arithmetic sequence, say {an} with a common difference d = -5 and the first term a = 1. Thus, the nth term formula for this arithmetic sequence is an = a + (n - 1)d = 1 -5(n - 1) = -5n + 6. Therefore, we can find any nth term of the given sequence by using the formula, nth term = 4n2 - 5n + 6 (check, for n = 1, 2, 3, 4, 5, 6, ... and you'll obtain the given sequence)
What is the fifth Nth term of 10-N squared?
2500, 100n2Restate the question: what are the 5th and nth term of (10n)2?If this is not your question, please clarify and resubmit the question.Assuming the first term is when n=1, then the 5th term is (10x5)2 = (50)2 =2500.The nth term would be just (10n)2, although you could expand and simplify to get (102)(n2) = 100n2.
