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��Х��W��ߪ��u�A�Ĥ@��ߪ��u��I�b (- 4, 0)�A �J�I�b (- 4, 4)�A�ĤG��ߪ��u��I�b (4, 4)�A�J�I�b (4, 0)�A �D��ߪ��u��I�C

��:�o�O�@�Ӱ򥻪��ߪ��u��D, �u�n�F�Ѧp��g�U�зǧΦ��ߪ��u��{��, �A��p�ߤ�{��D��I�Y�i.

�n�g�U�зǦ��ߪ��u��{��Ĥ@�B�N�O�n��P�_��ߪ��u��}�f��V�O�W�U�άO��k, ��۴N�O�D�X�J�Z. �Y��I��Ь� (a, b) �B��}�f�V�W�ΦV�U�h��{�� (x - a)² = 4c(y - b), �䤤 c ��J�Z. �J�Z c ��Ȭ��I�M�J�I�Z��, �Ӷ}�f�V�W�� c ��; �}�f�V�U�� c ��t. �Y��I��Ь� (a, b) �B��}�f�V��ΦV�k�h��{�� (y - b)² = 4c(x - a), �䤤�J�Z c ��Ȭ��I�M�J�I�Z��, �Ӷ}�f�V�k�� c ��; �}�f�V�� c ��t. �]��Y��D�@�зǧΦ��ߪ��u��I�M�J�I��, �N�i�H��W�g�U��{��.

��D�Ĥ@��ߪ��u��I�b (- 4, 0) �ӵJ�I�b (- 4, 4), �Ѧ��J�I�b��I��W��, �]�N�O�}�f�V�W��ߪ��u��{�� (x + 4)² = 4cy, �� c ��Ȭ� (- 4, 0) �M (- 4, 4) ��Z��B c ��, �G�o c = 4. �P�z��ĤG��ߪ��u��{�� (x - 4)² = 4c'(y - 4), �䤤 c' = - 4. �n�D��G�ߪ��u��I�Y��p�ߤ�{��:

$\displaystyle \left\{\vphantom{ \begin{array}{rl} (x+4)^2 &=16y\\ (x-4)^2& =-16(y-4)\\ \end{array}%% }\right.$ $\displaystyle \begin{array}{rl} (x+4)^2 &=16y\\ (x-4)^2& =-16(y-4)\\ \end{array}$

�⦡�ۥ[�i�o 2(x² + 16) = 64, �G�o x = 4 �� x = - 4. �� x = 4 �ɥN�^�Ĥ@��o y = 4, �ӷ� x = - 4 �ɥN�^�Ĥ@��o y = 0. �G��I�� (4, 4) �M (- 4, 0).

��X�~�j�Ҥ��߼ƾǸ��D�ҤF�X��G��u�Ωw�q��e��B�z��D. �򥻤W��ǰ��D�ҵ��T��, ��D��I�M�J�I��F, �Ωw�q��k�B�z�u��L�A��ɤ@��зǫ��ߪ��u��{��, ��L��n�Ωw�q�Ӹ��D. �Y��Τ�{��Ωw�q�B�z�G��u��A��ɾ��쪺�P��, �i�Ѧ�``97 �Ǧ~��Ҽƾǥ�''�h��D 8 ��ѻ�. ��D�Y�w�n�M�w�q��W, �ڭ̥i��X�Ĥ@��M�ĤG��ߪ��u��ǽu��O�� y = - 4 �M y = 8, �ӲĤ@��ߪ��u��I (- 4, 0) ��ĤG��ߪ��u��J�I (4, 0) ��Z��M��ĤG��ߪ��u��ǽu y = 8 ��Z��Ҭ� 8, �G�� (- 4, 0) �]�b�ĤG��ߪ��u�W (�ƹ�W�Ĥ@��ߪ��u��I��ĤG��ߪ��u��J��W��@�Ӻ��I). �P�z�i�o�ĤG��ߪ��u��I�]�b�Ĥ@��ߪ��u�W. �Ѧ��i�o (4, 4) �M (- 4, 0) �Ҭ��G�ߪ��u��I, ��o�å��^��o�Ӱ��D, �]��å��|��L��I. �ҥH�ڭ̵̨M�n�^�k��Ѥ�{��, ��@�Ӷ}�f�V�W��ߪ��u�M�}�f�V�U��ߪ��u�̦h�u�঳��ӥ��I, �~�⧹��^��D.

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Li 2008-08-16