Succession limit

[Anakin_99]

Hi guys I can't really understand what is wrong with my asymptotic, can u help me ? sorry if me english is so bad. Answer should be 5/2

 

[Dr.Peterson]

From the second line to the third, you ignored the fact that the radical is being multiplied by 2n.

I would just divide the numerator and denominator by n at the start, similar to what you did at the end.

 

[lex]

Yes, your second line should be:

[MATH]a_n=\frac{-12n+2n\left(\left(1-\frac{5}{4n}-\frac{5}{4n^2}\right)^\frac{1}{2}\ -1\right)+2n+3}{11-4n}[/MATH]
and it all works then.

 

[Anakin_99]

From the second line to the third, you ignored the fact that the radical is being multiplied by 2n.

I would just divide the numerator and denominator by n at the start, similar to what you did at the end.

Yes, your second line should be:

[MATH]a_n=\frac{-12n+2n\left(\left(1-\frac{5}{4n}-\frac{5}{4n^2}\right)^\frac{1}{2}\ -1\right)+2n+3}{11-4n}[/MATH]
and it all works then.

thank you very much I could never get it thanks

 

[Anakin_99]

Yes, your second line should be:

[MATH]a_n=\frac{-12n+2n\left(\left(1-\frac{5}{4n}-\frac{5}{4n^2}\right)^\frac{1}{2}\ -1\right)+2n+3}{11-4n}[/MATH]
and it all works then.

thank u man

 

[lex]

No problem. De niente.