数学问题请教

zipp_882000

find the limit

1)     lim         1/n (sin pie/2n+sin 2pie/2n+.....+sin npie/2n )
     n->infinity

2) lim            1/n^2  (sqrt(n^2-1^2 +sqrt(n^2-2^2) +.........sqrt(n^2 - n^2)
   n->infinity



find the integration of

1)(x+1)/(x^2+2x+3)

antimatter

integration of (x+1)/(x^2+2x+3) = ln(x^2 + 2x + 3)/2

puangenlun

find the limit

1)     lim         1/n (sin pie/2n+sin 2pie/2n+...+sin npie/2n )=2/pi
     n->infinity

2) lim            1/n^2  (sqrt(n^2-1^2 +sqrt(n^2-2^2) +...+sqrt(n^2 - n^2)=pi/4
   n->infinity


Method:
http://en.wikipedia.org/wiki/Integral
Bahagian: 3 Introduction