[3]
Sn=cos1+cos2+cos3+cos4+....+cosn
Find \lim_{n\rightarrow \infty}\frac{S_{n}}{n}
-
UP 0 DOWN 0 1 20
20 Answers
OH!!!
he he.....
i thot the first pink Akand got was for Q1....
NIce GOOGLY huh!!! [9]
and ya Q1 mein zero isliye aaya na kyunki Sum of n Roots of unity = 0 (for n>1
Q.1
are upar me .. sin () cos() hai usko infinity se divide karnege to zero hi naa aega...
[7] wat? kis post ki baat kar raheho priyam
are upar me .. sin () cos() hai usko infinity se divide karnege to zero hi naa aega...
Yah true.....
I gave the ans for n+1 terms.... with a lil calc mist. LOL.....
and ya Q1 mein zero isliye aaya na kyunki Sum of n Roots of unity = 0 (for n>1)
DUDEsss : is da ans to 2nd part = \cos ((2A + nB)/2)*\sin ((n+2)B/2)/sin(B/2)
yes bhaiya i understand........ (sorry who ek or thread .....
wo patanahi main kuch or soch raha tha.)
Philip this is a standard trick... try to see that you understand it :)
It just kills some of the dirty tough looking summations. :)
so....Sn=real(ei/1-ei)
so the limit becomes...
I=real(ei/1-ei)/n
=(cos1-cos21-sin21)/n(1+cos21+2cos1+sin21)
= (cos1-1)/n(2+2cos1)
..........then i dont kno........ wel thanks to PRIYAM...
I forgot 1/∞=0...hehehehehe
eiθ=cosθ+isinθ
so......
ei+e2i...eni=cos1+cos2+...cosn+i(sin1+sin2...sinn)
real(Σeir)=Sn