{"id":266,"date":"2012-01-21T22:41:51","date_gmt":"2012-01-21T13:41:51","guid":{"rendered":"http:\/\/roundown.main.jp\/nyushi\/?p=266"},"modified":"2021-03-24T09:35:56","modified_gmt":"2021-03-24T00:35:56","slug":"kyr200804","status":"publish","type":"post","link":"https:\/\/www.roundown.net\/nyushi\/kyr200804\/","title":{"rendered":"\u4eac\u5927\u7406\u7cfb\u4e592008\uff1a\u7b2c4\u554f"},"content":{"rendered":"<hr \/>\n<p>\u5b9a\u6570 \\(a\\) \u306f\u5b9f\u6570\u3067\u3042\u308b\u3068\u3059\u308b. \u95a2\u6570 \\(y= | x^2-2 |\\) \u3068 \\(y= | 2x^2+ax-1 |\\) \u306e\u30b0\u30e9\u30d5\u306e\u5171\u6709\u70b9\u306f\u3044\u304f\u3064\u3042\u308b\u304b. \\(a\\) \u306e\u5024\u306b\u3088\u3063\u3066\u5206\u985e\u305b\u3088.<\/p>\r\n<hr>\r\n<!--more-->\r\n<h4>\u3010 \u89e3 \u7b54 \u3011<\/h4>\r\n<p>\\[\\begin{align}\r\n| x^2-2 | = | 2x^2+ax-1 | & \\\\\r\n\\text{\u2234} \\quad ( 2x^2+ax-1 )^2 -( x^2-2 )^2 & =0 \\\\\r\n\\text{\u2234} \\quad ( 3x^2+ax-3 )( x^2+ax+1 ) & = 0\r\n\\end{align}\\]\r\n\u3057\u305f\u304c\u3063\u3066, \\(3x^2+ax-3 =0 \\quad ... [1]\\) , \\(x^2+ax+1 =0 \\quad ... [2]\\) \u306e\u89e3\u306e\u500b\u6570\u3092\u8003\u3048\u308c\u3070\u3088\u3044.<\/p>\r\n<ol>\r\n<li><p><strong>1*<\/strong>\u3000[1]\u306e\u89e3\u306e\u500b\u6570\u306b\u3064\u3044\u3066<br \/>\r\n\u5224\u5225\u5f0f\u3092 \\(D _ 1\\) \u3068\u304a\u304f\u3068\r\n\\[\r\nD _ 1 = a^2 +36 \\gt 0\r\n\\]\r\n\u3086\u3048\u306b, \\(a\\) \u306e\u5024\u306b\u3088\u3089\u305a, \u89e3\u3092 \\(2\\) \u500b\u3082\u3064.<\/p><\/li>\r\n<li><p><strong>2*<\/strong>\u3000[2]\u306e\u89e3\u306e\u500b\u6570\u306b\u3064\u3044\u3066\r\n\u5224\u5225\u5f0f\u3092 \\(D _ 2\\) \u3068\u304a\u304f\u3068\r\n\\[\r\nD _ 2 = a^2 -4 = (a+2)(a-2)\r\n\\]\r\n\u3086\u3048\u306b, \u89e3\u306e\u500b\u6570\u306f\r\n\\[\r\n\\left\\{ \\begin{array}{ll} 2 & ( a \\lt -2 , \\ 2 \\lt a \\text{\u306e\u3068\u304d} ) \\\\ 1 & ( a= \\pm 2 \\text{\u306e\u3068\u304d} ) \\\\ 0 & ( -2 \\lt a \\lt 2 \\text{\u306e\u3068\u304d} ) \\end{array} \\right.\r\n\\]<\/li>\r\n<li><p><strong>3*<\/strong>\u3000[1]\u3068[2]\u304c\u540c\u3058\u89e3\u3092\u3082\u3064\u3068\u304d<br \/>\r\n\u8fba\u3005\u3092\u5dee\u3057\u5f15\u304f\u3068\r\n\\[\\begin{align}\r\n2x^2 -4 & = 0 \\\\\r\n\\text{\u2234} \\quad x & =\\pm \\dfrac{\\sqrt{2}}{2}\r\n\\end{align}\\]\r\n\u3053\u306e\u3068\u304d\r\n\\[\\begin{align}\r\n\\dfrac{1}{2} \\pm \\dfrac{\\sqrt{2} a}{2} +1 & =0 \\\\\r\n\\text{\u2234} \\quad a & = \\pm \\dfrac{3 \\sqrt{2}}{2}\r\n\\end{align}\\]<\/li>\r\n<\/ol>\r\n<p>\u4ee5\u4e0a\u3088\u308a, \u5171\u6709\u70b9\u306e\u500b\u6570\u306f\r\n\\[\r\n\\underline{\\left\\{ \\begin{array}{ll} 4 & \\left( a \\lt -\\dfrac{3 \\sqrt{2}}{2} , \\ -\\dfrac{3 \\sqrt{2}}{2} \\lt a \\lt -2 , \\ 2 \\lt a \\lt \\dfrac{3 \\sqrt{2}}{2} , \\ \\dfrac{3 \\sqrt{2}}{2} \\lt a \\text{\u306e\u3068\u304d} \\right) \\\\ 3 & \\left( a= \\pm 2 \\text{\u306e\u3068\u304d} \\right) \\\\ 2 & \\left( a =\\pm \\dfrac{3 \\sqrt{2}}{2} , \\ -2 \\lt a \\lt 2 \\text{\u306e\u3068\u304d} \\right) \\end{array} \\right.}\r\n\\]\r\n","protected":false},"excerpt":{"rendered":"\u5b9a\u6570 \\(a\\) \u306f\u5b9f\u6570\u3067\u3042\u308b\u3068\u3059\u308b. \u95a2\u6570 \\(y= | x^2-2 |\\) \u3068 \\(y= | 2x^2+ax-1 |\\) \u306e\u30b0\u30e9\u30d5\u306e\u5171\u6709\u70b9\u306f\u3044\u304f\u3064\u3042\u308b\u304b. \\(a\\) \u306e\u5024\u306b\u3088\u3063\u3066\u5206\u985e\u305b\u3088.","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":[49],"tags":[140,16],"class_list":["post-266","post","type-post","status-publish","format-standard","hentry","category-kyoto_r_2008","tag-kyoto_r","tag-16"],"_links":{"self":[{"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/posts\/266","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=266"}],"version-history":[{"count":0,"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/posts\/266\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/media?parent=266"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/categories?post=266"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.roundown.net\/nyushi\/wp-json\/wp\/v2\/tags?post=266"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}