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			<title># 三角関数の対称式の値｜レベル別演習18問【Level A・B・C】</title>
			<pubDate><![CDATA[Tue, 26 May 2026 08:19:09 +0000]]></pubDate>
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			<title># 三角関数を含む等式の証明｜レベル別演習18問【Level A・B・C】</title>
			<pubDate><![CDATA[Tue, 26 May 2026 08:14:24 +0000]]></pubDate>
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			<title># 倍角の公式・半角の公式｜レベル別演習18問【Level A・B・C】</title>
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			<title>三角形の形の判定｜$a^2\cos A\sin B = b^2\cos B\sin A$ の解き方</title>
			<pubDate><![CDATA[Sun, 17 May 2026 03:38:31 +0000]]></pubDate>
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			<title>二次関数が $x$ 軸と交わる条件｜正の部分・正負両方の場合分け</title>
			<pubDate><![CDATA[Mon, 18 May 2026 13:07:42 +0000]]></pubDate>
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			<title># 【化学基礎】Fe²⁺の定量｜過マンガン酸カリウム滴定とイオン反応式</title>
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			<title># 二次関数の最大値・最小値（定義域の一端が動く）｜レベル別演習18問【Level A・B・C】</title>
			<pubDate><![CDATA[Mon, 11 May 2026 13:12:17 +0000]]></pubDate>
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			<pubDate><![CDATA[Fri, 15 May 2026 15:17:03 +0000]]></pubDate>
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			<title># 二次関数の最大値・最小値（文字定数・定義域）｜弱点克服18問</title>
			<pubDate><![CDATA[Fri, 15 May 2026 14:37:24 +0000]]></pubDate>
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			<pubDate><![CDATA[Sun, 10 May 2026 09:55:12 +0000]]></pubDate>
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			<pubDate><![CDATA[Tue, 05 May 2026 10:24:57 +0000]]></pubDate>
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			<title>**$y=\tan x$ と $y=\tan 3x$ のグラフ**の、漸近線の並べ方・周期・交点の一般解</title>
			<pubDate><![CDATA[Sun, 10 May 2026 09:52:35 +0000]]></pubDate>
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			<pubDate><![CDATA[Sun, 10 May 2026 09:50:26 +0000]]></pubDate>
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			<pubDate><![CDATA[Sun, 03 May 2026 06:49:42 +0000]]></pubDate>
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			<pubDate><![CDATA[Sun, 03 May 2026 06:44:51 +0000]]></pubDate>
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			<pubDate><![CDATA[Sun, 03 May 2026 06:24:25 +0000]]></pubDate>
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			<pubDate><![CDATA[Sat, 21 Feb 2026 13:55:15 +0000]]></pubDate>
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			<pubDate><![CDATA[Sat, 21 Feb 2026 13:48:42 +0000]]></pubDate>
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