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Grade 12th PassDifferential Calculus

lim n→∞ (2n+1 + 3n+1)/(2n + 3n) is equal to (a) 2 (b)3 (c) 5 (D) none. explain pls.

Profile image of Aditi Bhatnagar
14 Years agoGrade 12th Pass
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3 Answers

Profile image of RAJORSHI PAUL
14 Years ago

2^(n+1)+3^(n+1) =3^(n+1){(2/3)^(n+1) +1}

2^n+3^n =3^n{(2/3)^n +1}

As n tends to infinity (2/3)^n tends to 0

So the required limit is 3

 

Profile image of Chetan Mandayam Nayakar
14 Years ago

(2n+1 +3n+1)/(2n +3n)=2n+1/(2n + 3n)+3n+1/(2n + 3n)=2/(1+(3/2)n)+3/(3+(2/3)n)=0+1=1

 

Profile image of jitender lakhanpal
14 Years ago

Dear Aditi,

 

correct answer is 3 as (2/3)n   where n is ∞ is 0

so if we take 3n+1  from numerator and 3n  is denominator so we get (2/3)n  form

 

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