当X趋近0时,sin(1/x)=?
x\u8d8b\u8fd1\u4e0e0\u65f6\u3002\u3002\u3002sin<1\u6bd4x>\u7684\u6781\u9650\u662f\uff1f\u8be5\u95ee\u9898\u7684\u6781\u9650\u662f\u4e0d\u5b58\u5728\u7684\uff0c\u5982\u4f55\u8bf4\u660e\u5176\u6781\u9650\u5982\u4f55\u4e0d\u5b58\u5728\u6211\u60f3\u66f4\u91cd\u8981\u3002
\u76f4\u7ebf\u4e0a\u4e00\u70b9\u6781\u9650\u5b58\u5728\u7684\u5145\u5206\u5fc5\u8981\u6761\u4ef6\u662ff(a+)=f(a-)\uff0c\u5373\u67d0\u70b9\u7684\u5de6\u53f3\u6781\u9650\u76f8\u7b49\u3002
\u5f53x\u21920+\u65f6\uff0c1/x\u2192+\u221e\uff0c\u663e\u7136sin(1/x)\u503c\u5728\u3010-1,1\u3011\u4e4b\u95f4\u4e0d\u56fa\u5b9a\u3002
\u540c\u7406\u5f53x\u21920-\u65f6\uff0c1/x\u2192-\u221e\uff0csin(1/x)\u7684\u6781\u9650\u4e5f\u4e0d\u5b58\u5728\u3002
\u7efc\u4e0a\uff0c\u539f\u95ee\u9898\u65e0\u6781\u9650
x/sin(2x)
=1/2*2x/sin(2x)
\u7d20\u6781\u9650=1/2*1=1/2
\uff081+\uff083/x\uff09\uff09^x
=[\uff081+\uff083/x\uff09\uff09^(x/3)]³
\u6240\u4ee5\u6781\u9650=e³
没答案，因为1/x趋近无穷大，此时sin函数不趋向一个确定的数
x→0,sin(1/x)没有极限
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