求极限为什么这个极限不存在
\u6781\u9650\u4e0d\u5b58\u5728\u54ea\u4e9b\u60c5\u51b5\uff1f\uff01\u60c5\u51b51\u3001\u5de6\u53f3\u6781\u9650\u4e0d\u76f8\u7b49\u3002
\u60c5\u51b52\u3001\u6781\u9650\u4e3a\u65e0\u7a77\u3002
\u6781\u9650\u67d0\u4e00\u4e2a\u51fd\u6570\u4e2d\u7684\u67d0\u4e00\u4e2a\u53d8\u91cf\uff0c\u6b64\u53d8\u91cf\u5728\u53d8\u5927\uff08\u6216\u8005\u53d8\u5c0f\uff09\u7684\u6c38\u8fdc\u53d8\u5316\u7684\u8fc7\u7a0b\u4e2d\uff0c\u9010\u6e10\u5411\u67d0\u4e00\u4e2a\u786e\u5b9a\u7684\u6570\u503cA\u4e0d\u65ad\u5730\u903c\u8fd1\u800c\u201c\u6c38\u8fdc\u4e0d\u80fd\u591f\u91cd\u5408\u5230A\u201d\u7684\u8fc7\u7a0b\u3002
\u6781\u9650\u601d\u60f3\u662f\u5fae\u79ef\u5206\u7684\u57fa\u672c\u601d\u60f3\uff0c\u662f\u6570\u5b66\u5206\u6790\u4e2d\u7684\u4e00\u7cfb\u5217\u91cd\u8981\u6982\u5ff5\uff0c\u5982\u51fd\u6570\u7684\u8fde\u7eed\u6027\u3001\u5bfc\u6570\uff08\u4e3a0\u5f97\u5230\u6781\u5927\u503c\uff09\u4ee5\u53ca\u5b9a\u79ef\u5206\u7b49\u7b49\u90fd\u662f\u501f\u52a9\u4e8e\u6781\u9650\u6765\u5b9a\u4e49\u7684\u3002
\u6269\u5c55\u8d44\u6599\uff1a
\u6781\u9650\u7684\u6027\u8d28\uff1a
1\u3001\u552f\u4e00\u6027\uff1a\u82e5\u6570\u5217\u7684\u6781\u9650\u5b58\u5728\uff0c\u5219\u6781\u9650\u503c\u662f\u552f\u4e00\u7684\uff0c\u4e14\u5b83\u7684\u4efb\u4f55\u5b50\u5217\u7684\u6781\u9650\u4e0e\u539f\u6570\u5217\u7684\u76f8\u7b49\u3002
2\u3001\u6709\u754c\u6027\uff1a\u5982\u679c\u4e00\u4e2a\u6570\u5217\u2019\u6536\u655b\u2018\uff08\u6709\u6781\u9650\uff09\uff0c\u90a3\u4e48\u8fd9\u4e2a\u6570\u5217\u4e00\u5b9a\u6709\u754c\u3002\u4f46\u662f\u5982\u679c\u4e00\u4e2a\u6570\u5217\u6709\u754c\uff0c\u8fd9\u4e2a\u6570\u5217\u672a\u5fc5\u6536\u655b\u3002
3\u3001\u548c\u5b9e\u6570\u8fd0\u7b97\u7684\u76f8\u5bb9\u6027\uff1a\u8b6c\u5982\uff1a\u5982\u679c\u4e24\u4e2a\u6570\u5217{xn} \uff0c{yn} \u90fd\u6536\u655b\uff0c\u90a3\u4e48\u6570\u5217{xn+yn}\u4e5f\u6536\u655b\uff0c\u800c\u4e14\u5b83\u7684\u6781\u9650\u7b49\u4e8e{xn} \u7684\u6781\u9650\u548c{yn} \u7684\u6781\u9650\u7684\u548c\u3002
4\u3001\u4e0e\u5b50\u5217\u7684\u5173\u7cfb\uff1a\u6570\u5217{xn} \u4e0e\u5b83\u7684\u4efb\u4e00\u5e73\u51e1\u5b50\u5217\u540c\u4e3a\u6536\u655b\u6216\u53d1\u6563\uff0c\u4e14\u5728\u6536\u655b\u65f6\u6709\u76f8\u540c\u7684\u6781\u9650\uff1b\u6570\u5217{xn} \u6536\u655b\u7684\u5145\u8981\u6761\u4ef6\u662f\uff1a\u6570\u5217{xn} \u7684\u4efb\u4f55\u975e\u5e73\u51e1\u5b50\u5217\u90fd\u6536\u655b\u3002
\u53c2\u8003\u8d44\u6599\u6765\u6e90\uff1a\u767e\u5ea6\u767e\u79d1-\u6781\u9650
\u3000\u3000A. g.e. = lim(x\u2192inf.)(x - 1/x) = inf.\uff0c
\u3000\u3000\u5982\u679c\u8ba4\u4e3a\u65e0\u7a77\u5927\uff08inf.\uff09 \u662f\u4e0d\u5b58\u5728\u7684\u8bdd\u3002
因为分母无限趋于零！
绛旓細x^(-1/3)cos1/x 鍥犱负鏋侀檺涓嶅瓨鍦 cos1/x 鍦▁瓒嬭繎0锛宑os1/x闇囪崱锛岃屼笖涓嶆槸鏃犵┓灏忎箻浠ユ湁鐣岀殑鎯呭喌锛屾墍浠ユ瀬闄愪笉瀛樺湪
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