��

�� 1.2 ��

��

��Ϳ��Ƥ��Ȥ��롣

�γƸ�

�ˤ��ơ� ��

�θ� (

�Ƚ񤫤��) ��Ϥä��(��̤��) ��ޤäƤ��Ȥ��

��

�ؤ�

�Ȥ������ Ƥ��ȸ�� ˡ��ΤȤ��

��

��(�ޤ��ϻϽ��)�Ȥ��

��

�� ȸ��

�� 1.1 �Ĥ��Τ��Τ��ΤΡ��ּ��Τ褦�ʤ�ΡפˤĤ��ƹͤ��褦��

ʿ�̻��ѷ�� $)\ni \Delta \mapsto (a,b,c) (=$ $&Delta#Delta;$ �λ�� $)\in$ $\mbox{${\mathbb{R}}$}$
ʿ�̻��ѷ�� $)\ni \Delta \mapsto (a+b+c)\in$ $\mbox{${\mathbb{R}}$}$ $% latex2html id marker 915 $ \qquad ($$ $a,b,c$ �� $&Delta#Delta;$ �λ��
$\mbox{${\mathbb{R}}$}$ $% latex2html id marker 919 $ \ni x \mapsto \sqrt{x} \in$$ $\mbox{${\mathbb{R}}$}$
$\mbox{${\mathbb{R}}$}$ $% latex2html id marker 923 $ _{>0} \ni x \mapsto \sqrt{x} \in$$ $\mbox{${\mathbb{R}}$}$

��Τ��(2)�ϼ��Ǥ��(��ޤ��Ƥ��)�� (1),(3) �ϼ��ǤϤʤ�(��ޤ��Ƥ��ʤ�)�� (4)�ˤĤ��Ƥ�ʿ��Τ�Τ�Ȥ�פ��«��Ƥ�� ޤ��Ƥ��롣��Τ褦�ˡ� ��ΤޤޤǤϤ��ޤ��Ƥ��ʤ��ΤǤ⡢ ��դ��䤦��Ȥˤ�äƤ��ޤ��Ǥ��Ƥ��褦�˽��Ǥ��礬��롣

�� 1.1 �Ĥ��Τ褦�ʼ��

$\mbox{${\mathbb{Q}}$}$ $\to {\mbox{${\mathbb{Z}}$}}$ (ʬ��Ф��Ƥ��ʬ��Ϳ��)��ꤿ��

$\displaystyle f(1/3)=3, f(2/5)=5, f(355/113)=113,\dots$

(*)

��ΤȤ��

��

$% latex2html id marker 939 $\displaystyle f(m/n)=n \qquad (m,n \in {\mbox{${\mathbb{Z}}$}}, n\neq 0) $$

��褦�Ȥ��Ƥ⡢��Ϥ��ޤ��Ƥ��ʤ��Ȥ� ��ʤ��
(1)��ơ� (*) �� ʤ��

����

��