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高考数学不等式比较技巧作差作商法实战口诀
鍝庯紒姣忔鑰冭瘯鐪嬪埌"姣旇緝a虏+1鍜?a鐨勫ぇ灏?杩欑棰橈紝鏄笉鏄€绘兂鎽旂瑪锛熷埆鎱岋紒浠婂ぉ鍜变滑鐢ㄤ袱澶х粷鎷?鍏彞鍙h瘈锛屼繚鍑嗚浣犵湅瀹屽氨鑳戒笂鎵嬶紝杩炴暟瀛﹁浠h〃閮藉緱鍠婁綘"澶х"锛?/p>
涓€銆佷綔宸硶锛氭瘮澶у皬鐣岀殑"涓囪兘閽ュ寵"
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涓句釜鏍楀瓙馃尠锛氭瘮杈?025鍜?024璋佸ぇ锛熺洿鎺?025-2024=1>0锛岀鎳?025鏇村ぇ銆備絾閬囧埌鍍忔瘮杈冣垰3鍜?.732杩欑杩戜技鍊兼椂锛屼綔宸硶鑳藉噯纭憡璇変綘鈭?鈮?.73205锛?.732銆?/p>
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鈥?strong>鈥嬫搷浣滄墜鍐屸€?/strong>鈥嬶細
- 浣滃晢鈫掑寲绠€鈫掑拰1姣斿ぇ灏?/li>
- 姝f暟淇濇寔鏂瑰悜锛岃礋鏁拌寰楀弽杞?/li>
涓句釜瀹炴垬妗堜緥锛氭瘮杈僱og鈧?鍜宭og鈧?銆傚厛鎹㈡垚鍚屽簳锛?br/>
log鈧?=1/log鈧?锛宭og鈧?=2log鈧?
浣滃晢寰?1/log鈧?)/(2log鈧?)=1/(2(log鈧?)虏)
鍥犱负log鈧?鈮?.631锛屾墍浠ョ粨鏋溾増1.25>1锛屾晠log鈧?锛瀕og鈧?
鈥?strong>鈥嬫浜¢櫡闃扁€?/strong>鈥嬶細
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- 鎸囨暟娣锋穯锛氭瘮杈?鈦垮拰3鈦挎椂锛屼綔鍟嗗緱(2/3)鈦匡紝杩欐椂鍊欒鐪媙姝h礋
涓夈€佷綔宸畍s浣滃晢锛氳皝鎵嶆槸鐪熺帇鑰咃紵
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鍥涖€佸叚澶у疄鎴樺彛璇€
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涓句釜搴旂敤妗堜緥锛氭瘮杈?024鈦垮拰2025鈦匡紙n>0锛夈€傜敤鍙h瘈5鍏堜綔鍟嗭細(2024/2025)鈦?lt;1锛堝洜涓?024<2025锛夛紝鐩存帴寰?024鈦?lt;2025鈦裤€?/p>
浣犻棶鎴戠瓟
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灏忕紪瑙傜偣
鏁欎功鍗佸勾锛屽彂鐜板鐢熸渶甯哥姱涓変釜閿欙細
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