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Let {an}, {bn} and {cn} be sequences of real numbers such that bn = a2n and cn = a2n+1. Then {an} is convergent
  • a)
    implies both {bn} and {cn} are convergent
  • b)
    implies {bn} is convergent but {cn} need not be convergent
  • c)
    implies {cn} is convergent but {bn} need not be convergent 
  • d)
    if both {bn} and {cn} are convergent
Correct answer is option 'A'. Can you explain this answer?
Verified Answer
Let {an}, {bn} and {cn} be sequences of real numbers such that bn = a2...
If {an} is convergent, 
Then {bn} and {cn} both are convergent. because {bn} and {cn} are sub sequence of {an}
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Most Upvoted Answer
Let {an}, {bn} and {cn} be sequences of real numbers such that bn = a2...
Explanation:

To prove that option A is the correct answer, we need to show that if the sequence {an} is convergent, then both {bn} and {cn} are also convergent.

Convergence of a Sequence:
A sequence {an} is said to be convergent if there exists a real number L such that for every positive number ε, there exists a positive integer N such that for all n ≥ N, |an - L| < />

To prove that {an} implies both {bn} and {cn} are convergent, we need to show that for every ε > 0, there exists a positive integer N1 and N2 such that for all n ≥ N1, |bn - L1| < ε="" and="" for="" all="" n="" ≥="" n2,="" |cn="" -="" l2|="" />< />

Proof:
Let's assume that {an} is convergent. Then, there exists a real number L such that for every ε > 0, there exists a positive integer N such that for all n ≥ N, |an - L| < />

Convergence of {bn}:
Now, let's consider the sequence {bn} = {a2n}. We need to show that {bn} is convergent. Let's choose an arbitrary ε > 0.

Since {an} is convergent, there exists a positive integer N1 such that for all n ≥ N1, |an - L| < />

Let's substitute n = 2k in the above inequality, where k is a positive integer.

|a2k - L| < />

Now, let's consider the difference between bn and L:

|bn - L| = |a2k - L|

Since n = 2k, we can rewrite the above inequality as:

|bn - L| < />

Therefore, for every ε > 0, there exists a positive integer N1 such that for all n ≥ N1, |bn - L| < ε.="" this="" shows="" that="" {bn}="" is="" />

Convergence of {cn}:
Now, let's consider the sequence {cn} = {a2n+1}. We need to show that {cn} is convergent. Let's choose an arbitrary ε > 0.

Since {an} is convergent, there exists a positive integer N2 such that for all n ≥ N2, |an - L| < />

Let's substitute n = 2k + 1 in the above inequality, where k is a positive integer.

|a2k+1 - L| < />

Now, let's consider the difference between cn and L:

|cn - L| = |a2k+1 - L|

Since n = 2k + 1, we can rewrite the above inequality as:

|cn - L| < />

Therefore, for every ε > 0, there exists a positive integer N2 such that for all n ≥ N2, |cn - L| < ε.="" this="" shows="" that="" {cn}="" is="" />

Conclusion:
Since we have shown that if {an} is convergent, then both {bn} and {cn} are convergent, the correct answer is option A.
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Let {an}, {bn} and {cn} be sequences of real numbers such that bn = a2n and cn = a2n+1. Then {an} is convergenta)implies both {bn} and {cn} are convergentb)implies {bn} is convergent but {cn} need not be convergentc)implies {cn} is convergent but {bn} need not be convergentd)if both {bn} and {cn} are convergentCorrect answer is option 'A'. Can you explain this answer?
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Let {an}, {bn} and {cn} be sequences of real numbers such that bn = a2n and cn = a2n+1. Then {an} is convergenta)implies both {bn} and {cn} are convergentb)implies {bn} is convergent but {cn} need not be convergentc)implies {cn} is convergent but {bn} need not be convergentd)if both {bn} and {cn} are convergentCorrect answer is option 'A'. Can you explain this answer? for Mathematics 2024 is part of Mathematics preparation. The Question and answers have been prepared according to the Mathematics exam syllabus. Information about Let {an}, {bn} and {cn} be sequences of real numbers such that bn = a2n and cn = a2n+1. Then {an} is convergenta)implies both {bn} and {cn} are convergentb)implies {bn} is convergent but {cn} need not be convergentc)implies {cn} is convergent but {bn} need not be convergentd)if both {bn} and {cn} are convergentCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for Mathematics 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Let {an}, {bn} and {cn} be sequences of real numbers such that bn = a2n and cn = a2n+1. Then {an} is convergenta)implies both {bn} and {cn} are convergentb)implies {bn} is convergent but {cn} need not be convergentc)implies {cn} is convergent but {bn} need not be convergentd)if both {bn} and {cn} are convergentCorrect answer is option 'A'. Can you explain this answer?.
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