limx趋近于无穷怎么算 极限limx趋近于无穷大
limx/1+x x\u8d8b\u8fd1\u4e8e\u65e0\u7a77 \u6b64\u6781\u9650\u662f\u591a\u5c11 \u600e\u4e48\u7b97lim(x->\u221e) x/(1+x)
~ lim(x->\u221e) x/x
= 1
\u6216\u6d1b\u5fc5\u8fbe\u6cd5\u5219
lim(x->\u221e) x/(1+x)
= lim(x->\u221e) 1/(0+1)
= 1
\u7531\u4e8e lim(x-+\u65e0\u7a77)x=+\u65e0\u7a77\uff0c lim(x-+\u65e0\u7a77)\uff081/x\uff09=0\u6240\u4ee5lim(x-+\u65e0\u7a77)[x^2+1)/x]^1/2= lim(x-+\u65e0\u7a77)[x+1/x]^1/2=+\u65e0\u7a77%D%A\u8ffd\u95ee\uff1a%D%A\u8fd9\u9898\u7684\u7b54\u6848\u662f\u6781\u9650\u4e0d\u5b58\u5728\u3002\u4e3a\u4ec0\u4e48%D%A\u56de\u7b54\uff1a%D%A\u7531\u4e8e lim(x-+\u65e0\u7a77)x=+\u65e0\u7a77\uff0c lim(x-+\u65e0\u7a77)\uff081/x\uff09=0\u6240\u4ee5lim(x-+\u65e0\u7a77)[x^2+1)/x]^1/2= lim(x-+\u65e0\u7a77)[x+1/x]^1/2=+\u65e0\u7a77\u6781\u9650\u8d8b\u4e8e\u65e0\u7a77\u5c31\u662f\u4e0d\u6536\u655b\uff0c\u4e5f\u5c31\u662f\u4e0d\u5b58\u5728%D%A\u8ffd\u95ee\uff1a%D%A\u6781\u9650\u8d8b\u4e8e\u65e0\u7a77\u5c31\u662f\u4e0d\u6536\u655b\uff0c\u4e5f\u5c31\u662f\u4e0d\u5b58\u5728\u3002 \u90a3\u4e3a\u4ec0\u4e48 \u6211\u505a\u7684\u8ba1\u7b97\u9898\u91cc\u9762\u6709\u5f88\u591a\u9898\u76ee\u6c42\u6781\u9650\u6700\u540e\u6c42\u5f97\u7684\u6781\u9650\u90fd\u662f\u65e0\u7a77\u554a\u3002\u6bd4\u5982\u8bf4\u8fd9\u9898limx\u8d8b\u5411\u4e8e\u65e0\u7a77\u5927(3x^3-x^2+2)/(2x^2+1)= \u65e0\u7a77\u5927\u3002\u4e0d\u662f\u8bf4\u6781\u9650\u8d8b\u4e8e\u65e0\u7a77\u5c31\u662f\u4e0d\u6536\u655b\uff0c\u4e5f\u5c31\u662f\u4e0d\u5b58\u5728\u3002\u95ee\u9898\u5c31\u51fa\u5728\u8fd9\u91cc\uff0c\u6211\u4e0a\u4e00\u9898\u6c42\u51fa\u7684\u7ed3\u679c\u4e5f\u662f\u65e0\u7a77\u5927\uff0c\u7b54\u6848\u8bf4\u4e0d\u5b58\u5728\u3002 \u540e\u9762\u8fd9\u9898\u6c42\u51fa\u7684\u7ed3\u679c\u5374\u662f\u6781\u9650\u4e3a\u65e0\u7a77\u5927\u3002\u8bf7\u8001\u5e08\u6307\u6559\uff01\u8c22\u8c22%D%A\u56de\u7b54\uff1a%D%A\u65e0\u7a77\u5927\uff0c\u632f\u8361\uff08\u6bd4\u5982sinx\uff09\u90fd\u662f\u4e0d\u5b58\u5728\uff1b\u4e0d\u5b58\u5728\u4e0d\u4e00\u5b9a\u4ee3\u8868\u65e0\u7a77\u5927\uff0c\u53ef\u4ee5\u662f\u632f\u8361\u8fd9\u79cd\uff1b\u65e0\u7a77\u5927\u4e00\u5b9a\u662f\u4e0d\u5b58\u5728%D%A
解：这个题目这样算
limx趋近于无穷这样算
lim（x→∞）x
=x→∞
=∞
limx趋近于无穷=∞
2x+1/x^2+1
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