■ピザの公平な分け方(その15)
a=arcsin(sin(π/8−α)/R)−arcsin(−sinα/R)
b=arcsin(sin(π/4−α)−arcsin(sin(π/8−α)/R)
c=arcsin(sin(3π/8−α)/R)−arcsin(sin(π/4−α)/R)
d=arcsin(cosα/R)−arcsin(3π/8−α)/R)
e=arcsin(cos(π/8−α)/R)−arcsin(cosα/R)
f=arcsin(sin(π/4−α)/R)−arcsin(cos(π/8−α)/R)
g=arcsin(cos(3π/8−α)/R)−arcsin(cos(π/4−α)/R)
h=arcsin(sinα/R)−arcsin(cos(3π/8−α)/R)
i=arcsin(−sin(π/8−α)/R)−arcsin(sinα/R)
j=arcsin(−sin(π/4−α)/R)−arcsin(−sin(π/8−α)/R)
k=arcsin(−sin(3π/8−α)/R)−arcsin(−sin(π/4−α)/R)
l=arcsin(−cosα/R)−arcsin(−sin(3π/8−α)/R)
m=arcsin(−cos(π/8−α)/R)−arcsin(−cosα/R)
n=arcsin(−sin(π/4−α)/R)−arcsin(−cos(π/8−α)/R)
o=arcsin(−cos(3π/8−α)/R)−arcsin(−cos(π/4−α)/R)
p=arcsin(−sinα/R)−arcsin(−cos(3π/8−α)/R)
a+i=0,b+j=0,c+k=0,d+l=0
m+e=0,n+f=0,o+g=0,p+h=0
a+c+e+g+i+k+m+o=b+d+f+h+j+l+n+pは成り立つ.
a+e+i+m=c+g+k+o=b+f+j+n=d+h+l+pも成り立つ.したがって,4人でも均等に分けることができる可能性がある.
===================================