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A sequence a1 , a2 ,…is defined such that each term is
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19 Jul 2019, 09:00
19 Jul 2019, 09:00
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A sequence \(a_1\), \(a_2\) ,…is defined such that each term is 3 less than the preceding term. Which of the following equations is consistent with this definition?
(A) \(a_{n+1} – 3 = a_n\)
(B) \(a_{n+1} + 3 = a_n\)
(C) \(3 – a_n = a_{n+1}\)
(D) \(3 – a_{n+1} = a_n\)
(E) \(a_n + 3 = a_{n+1}\)
(A) \(a_{n+1} – 3 = a_n\)
(B) \(a_{n+1} + 3 = a_n\)
(C) \(3 – a_n = a_{n+1}\)
(D) \(3 – a_{n+1} = a_n\)
(E) \(a_n + 3 = a_{n+1}\)
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Re: A sequence a1 , a2 ,…is defined such that each term is
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12 May 2020, 23:15
12 May 2020, 23:15
1
Carcass wrote:
A sequence \(a_1\), \(a_2\) ,…is defined such that each term is 3 less than the preceding term. Which of the following equations is consistent with this definition?
(A) \(a_{n+1} – 3 = a_n\)
(B) \(a_{n+1} + 3 = a_n\)
(C) \(3 – a_n = a_{n+1}\)
(D) \(3 – a_{n+1} = a_n\)
(E) \(a_n + 3 = a_{n+1}\)
(A) \(a_{n+1} – 3 = a_n\)
(B) \(a_{n+1} + 3 = a_n\)
(C) \(3 – a_n = a_{n+1}\)
(D) \(3 – a_{n+1} = a_n\)
(E) \(a_n + 3 = a_{n+1}\)
Each term is 3 less than the preceding term; thus:
a2 = a1 - 3
a3 = a2 - 3
a4 = a3 - 3 and so on
Thus, we have: a2 = a1 - 3, a3 = a1 - 6; a4 = a1 - 9 and so on
Thus: \(=> a_{n+1} = a_n - 3\)
Note:
=> a2 = a1 - 3 x 1, a3 = a1 - 3 x 2; a4 = a1 - 3 x 3 and so on
=> a2 = a1 - 3 x (2 - 1), a3 = a1 - 3 x (3 - 1); a4 = a1 - 3 x (4 - 1) and so on
Answer B
Re: A sequence a1 , a2 ,…is defined such that each term is
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31 May 2021, 02:23
31 May 2021, 02:23
1
a1,a2,a3,a4,........
where a2=a1-3
a3=a2-6
lets check the options we have n and n+1 in it so it means
a_(n+1)=a_n -3
a_n=a_(n+1)+3
option B is the answer.
where a2=a1-3
a3=a2-6
lets check the options we have n and n+1 in it so it means
a_(n+1)=a_n -3
a_n=a_(n+1)+3
option B is the answer.
