{"id":321,"date":"2012-02-25T20:34:01","date_gmt":"2012-02-25T11:34:01","guid":{"rendered":"http:\/\/roundown.main.jp\/nyushi\/?p=321"},"modified":"2021-11-04T14:48:09","modified_gmt":"2021-11-04T05:48:09","slug":"htb200803","status":"publish","type":"post","link":"https:\/\/www.roundown.net\/nyushi\/htb200803\/","title":{"rendered":"\u4e00\u6a4b\u59272008\uff1a\u7b2c3\u554f"},"content":{"rendered":"<hr \/>\n<p>\\(a\\) \u3092\u6b63\u306e\u5b9f\u6570\u3068\u3059\u308b.\r\n\u70b9 \\((x,y)\\) \u304c, \u4e0d\u7b49\u5f0f \\(x^2 \\leqq y \\leqq x\\) \u306e\u5b9a\u3081\u308b\u9818\u57df\u3092\u52d5\u304f\u3068\u304d, \u5e38\u306b \\(\\dfrac{1}{2} \\leqq (x-a)^2+y \\leqq 2\\) \u3068\u306a\u308b. \\(a\\) \u306e\u7bc4\u56f2\u3092\u6c42\u3081\u3088.<\/p>\r\n<hr \/>\r\n<h3>\u89e3\u7b54<\/h3>\r\n<p>\\(x^2 \\leqq y \\leqq x\\) ... [1] \u304c\u793a\u3059\u9818\u57df \\(D\\) \u306f, \u4e0b\u56f3\u659c\u7dda\u90e8.<\/p>\r\n<img decoding=\"async\" src=\"\/\/www.roundown.net\/nyushi\/wp-content\/uploads\/hitotsubashi_2008_03_01.png\" alt=\"hitotsubashi_2008_03_01\" class=\"aligncenter size-full\" \/>\r\n<p>\\(\\dfrac{1}{2} \\leqq (x-a)^2+y \\leqq 2\\) ... [2] \u3092\u5909\u5f62\u3059\u308b\u3068\r\n\\[\r\n-(x-a)^2 +\\dfrac{1}{2} \\leqq y \\leqq -(x-a)^2 +2\r\n\\]\r\n\u3086\u3048\u306b, [2] \u304c\u793a\u3059\u9818\u57df \\(C\\) \u306f \\(2\\) \u3064\u306e\u653e\u7269\u7dda\u306b\u631f\u307e\u308c\u305f\u4e0b\u56f3\u659c\u7dda\u90e8.<\/p>\r\n<img decoding=\"async\" src=\"\/\/www.roundown.net\/nyushi\/wp-content\/uploads\/hitotsubashi_2008_03_02.png\" alt=\"hitotsubashi_2008_03_02\" class=\"aligncenter size-full\" \/>\r\n<p>\u4ee5\u4e0a\u3088\u308a, \\(D\\) \u304c \\(C\\) \u304c\u542b\u307e\u308c\u308b\u3088\u3046\u306a, \\(a\\) \u306e\u7bc4\u56f2\u3092\u6c42\u3081\u308c\u3070\u3088\u3044.<br \/>\r\n\\(a\\) \u3059\u306a\u308f\u3061 \\(C\\) \u3092\u4f5c\u308b \\(2\\) \u3064\u306e\u653e\u7269\u7dda\u3092\u52d5\u304b\u3059\u3068\u304d, \\(D\\) \u3092\u542b\u3080\u304b\u3069\u3046\u304b\u306e\u5883\u754c\u3068\u306a\u308b\u306e\u306f, \u4ee5\u4e0b\u306e \\(2\\) \u3064\u306e\u5834\u5408\u304c\u8003\u3048\u3089\u308c\u308b.<\/p>\r\n<ol>\r\n<li><p><strong>1*<\/strong>\u3000\u4e0b\u306e\u653e\u7269\u7dda\u304c, \\(0 \\leqq x \\leqq 1\\) \u3067 \\(y=x^2\\) \u3068\u63a5\u3059\u308b\u3068\u304d.<\/p>\r\n<img decoding=\"async\" src=\"\/\/www.roundown.net\/nyushi\/wp-content\/uploads\/hitotsubashi_2008_03_03.png\" alt=\"hitotsubashi_2008_03_03\" class=\"aligncenter size-full\" \/><\/li>\r\n<li><p><strong>2*<\/strong>\u3000\u4e0a\u306e\u653e\u7269\u7dda\u306e \\(x \\leqq a\\) \u306e\u90e8\u5206\u304c, \u539f\u70b9\u3092\u901a\u308b\u3068\u304d.<p>\r\n<img decoding=\"async\" src=\"\/\/www.roundown.net\/nyushi\/wp-content\/uploads\/hitotsubashi_2008_03_04.png\" alt=\"hitotsubashi_2008_03_04\" class=\"aligncenter size-full\" \/><\/li>\r\n<\/ol>\r\n<p>\u305d\u308c\u305e\u308c\u306e\u5834\u5408\u306e \\(a\\) \u306e\u5024\u3092\u6c42\u3081\u308b.<\/p>\r\n<ol>\r\n<li><p><strong>1*<\/strong>\u306b\u3064\u3044\u3066<br \/>\r\n\\[\\begin{align}\r\n-(x-a)^2+\\dfrac{1}{2} & =x^2 \\\\\r\n4x^2 -4ax +2a^2 -1 & = 0\r\n\\end{align}\\]\r\n\u3053\u306e\u5224\u5225\u5f0f \\(E\\) \u306b\u3064\u3044\u3066\r\n\\[\\begin{align}\r\nE = (2a)^2 -4 \\left( 2a^2 -1 \\right) & = 0 \\\\\r\n4a^2 -4 & = 0 \\\\\r\n\\text{\u2234} \\quad a = 1\r\n\\end{align}\\]<\/li>\r\n<li><p><strong>2*<\/strong>\u306b\u3064\u3044\u3066<br \/>\r\n\\[\\begin{align}\r\n0 = -(0-a)^2 & +2 \\\\\r\n\\text{\u2234} \\quad a & = \\sqrt{2}\r\n\\end{align}\\]<\/li>\r\n<\/ol>\r\n<p>\u3088\u3063\u3066, \u6c42\u3081\u308b \\(a\\) \u306e\u7bc4\u56f2\u306f\r\n\\[\r\n\\underline{1 \\leqq a \\leqq \\sqrt{2}}\r\n\\]\r\n","protected":false},"excerpt":{"rendered":"\\(a\\) \u3092\u6b63\u306e\u5b9f\u6570\u3068\u3059\u308b. \u70b9 \\((x,y)\\) \u304c, \u4e0d\u7b49\u5f0f \\(x^2 \\leqq y \\leqq x\\) \u306e\u5b9a\u3081\u308b\u9818\u57df\u3092\u52d5\u304f\u3068\u304d, \u5e38\u306b \\(\\dfrac{1}{2} \\leqq (x-a)^2+y \\leq &hellip; <a href=\"https:\/\/www.roundown.net\/nyushi\/htb200803\/\">\u7d9a\u304d\u3092\u8aad\u3080 <span class=\"meta-nav\">&rarr;<\/span><\/a>","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"footnotes":""},"categories":[57],"tags":[146,16],"class_list":["post-321","post","type-post","status-publish","format-standard","hentry","category-hitotsubashi_2008","tag-hitotsubashi","tag-16"],"_links":{"self":[{"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/posts\/321","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/comments?post=321"}],"version-history":[{"count":0,"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/posts\/321\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/media?parent=321"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/categories?post=321"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/tags?post=321"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}