🚀 go-pugleaf

$@Gk86!w?^8&$G$9!#(J

In article <SANO.95Nov29140840@antares.ecn.fpu.ac.jp> sano@antares.ecn.fpu.ac.jp
(Kazuo Sano) writes: 
   >>1/2 + cos(t)+ cos(2t)+...= (1/2)sin(n-1/2)t / sin(1/2)
   >> $@!!!!!!!!!!!!!!!!!!!!!!!!(J= (1/2)[cos(n-1)t - cos(nt)] / (1-cost)
   >>
   >>$@$,J,$+$j$^$;$s!#$3$l$O%U!<%j%(5i?t$N<}B+$KI,MW$JDjM}$r(J
   >>$@Aj2CJ?6QAmOBK!$K$h$C$FF3$/:]$K$G$F$/$kEy<0$G$9!#%R%s%H(J
   >>$@$J$I$G$b7k9=$G$9$N$G$h$m$7$/$*4j$$$7$^$9(J$@!#(J

$@>HL@$7$?$$$N$OB?J,!"(J
1/2 + cos(t) + cos(2t) + ... + cos((n-1)t) = (1/2) sin((n-1/2)t) / sin(t/2)
$@$G$7$g$&!#(J

$@1&JU$r(J K(n) $@$H$*$$$F5"G<K!$G$G$-$^$9!#(J
$@!&(Jn=1 $@$N$H$-$O!"MF0W!#(J
$@!&(Jn=m $@$N$H$-$,@.N)$9$k$H$7$F(J$@!"(Jn=m+1$@$N$H$-$N@.N)$r<($;$PNI$$$N$G$9$,!"(J
  $@$=$N$?$a$K$O!"(JK(n+1) - K(n) = cos(n*t) $@$r$7$a$;$PNI$$!#(J
  $@$3$l$O!"$$$o$f$kOB@Q$N8x<0(J sin A - sin B = 2 * cos((A+B)/2) * sin((A-B)/2)
  $@$r;H$($PMF0W$G$9!#(J

$@#2HV(J$@$a$NEy9f$b4JC1$H;W$$$^$9$,!"$I$J$?$+$K>y$j$^$9!#(J
--
Kazuyuki Hagiwara @ Zuken, Inc.  Yokohama, Japan (hagiwara@zuken.co.jp)