两个无穷大量之和的极限仍为无穷大吗 2个无穷大与无穷大的乘积是无穷大吗?
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无穷小=无穷小=无穷小
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绛旓細2.鈶犲鏋滃綋x>0涓旀棤闄愬澶ф椂锛屽嚱鏁癴(x)鏃犻檺瓒嬩簬涓涓父鏁癆锛屽垯绉板綋x鈫+鈭炴椂鍑芥暟f(x)浠涓鏋侀檺.璁颁綔 f(x)鈫扐锕檟鈫+鈭烇箽.鈶″鏋滃綋x<0涓攛鐨勭粷瀵瑰兼棤闄愬澶ф椂锛屽嚱鏁癴(x)鏃犻檺瓒嬩簬涓涓父鏁癆锛屽垯绉板綋x鈫掞紞鈭炴椂鍑芥暟f(x)浠涓烘瀬闄.璁颁綔 f(x)鈫扐锕檟鈫掞紞鈭烇箽鎬ц川 涓や釜鏃犵┓澶ч噺涔嬪拰涓...
绛旓細渚嬪褰搙鈫0鐨勬椂鍊欙紝x鏄棤绌灏忥紝鑰1/x²鏄棤绌峰ぇ锛屼袱鑰呯殑涔樼Н1/x涔熸槸鏃犵┓澶ц屼笉鏄棤绌峰皬銆傛澶栧綋x鈫0鐨勬椂鍊欙紝x鏄棤绌峰皬锛1/x鏄棤绌峰ぇ锛屼袱鑰呯殑涔樼Н鏄鏋侀檺涓1鐨勫嚱鏁帮紝涓嶆槸鏃犵┓灏忋傛ц川 涓や釜鏃犵┓澶ч噺涔嬪拰涓嶄竴瀹氭槸鏃犵┓澶с傛湁鐣岄噺涓庢棤绌峰ぇ閲忕殑涔樼Н涓嶄竴瀹氭槸鏃犵┓澶э紙濡傚父鏁0灏辩畻鏄湁鐣屽嚱鏁帮級銆...
绛旓細2.鈶犲鏋滃綋x>0涓旀棤闄愬澶ф椂锛屽嚱鏁癴(x)鏃犻檺瓒嬩簬涓涓父鏁癆锛屽垯绉板綋x鈫+鈭炴椂鍑芥暟f(x)浠涓鏋侀檺.璁颁綔 f(x)鈫扐锕檟鈫+鈭烇箽.鈶″鏋滃綋x<0涓攛鐨勭粷瀵瑰兼棤闄愬澶ф椂锛屽嚱鏁癴(x)鏃犻檺瓒嬩簬涓涓父鏁癆锛屽垯绉板綋x鈫掞紞鈭炴椂鍑芥暟f(x)浠涓烘瀬闄.璁颁綔 f(x)鈫扐锕檟鈫掞紞鈭烇箽鎬ц川 涓や釜鏃犵┓澶ч噺涔嬪拰涓...
绛旓細2.鈶犲鏋滃綋x>0涓旀棤闄愬澶ф椂锛屽嚱鏁癴(x)鏃犻檺瓒嬩簬涓涓父鏁癆锛屽垯绉板綋x鈫+鈭炴椂鍑芥暟f(x)浠涓鏋侀檺.璁颁綔 f(x)鈫扐锕檟鈫+鈭烇箽.鈶″鏋滃綋x<0涓攛鐨勭粷瀵瑰兼棤闄愬澶ф椂锛屽嚱鏁癴(x)鏃犻檺瓒嬩簬涓涓父鏁癆锛屽垯绉板綋x鈫掞紞鈭炴椂鍑芥暟f(x)浠涓烘瀬闄.璁颁綔 f(x)鈫扐锕檟鈫掞紞鈭烇箽鎬ц川 涓や釜鏃犵┓澶ч噺涔嬪拰涓...
绛旓細涓や釜鏃犵┓灏忕殑鍜岋紝蹇呯劧鏄棤绌灏忥紝鍥犱负鏈夐檺涓棤绌峰皬鐩稿姞锛岃繕鏄棤绌峰皬銆涓や釜鏃犵┓澶т箣鍜锛屼笉涓瀹氭槸鏃犵┓澶э紝鍥犱负鏃犵┓澶ф湁+鈭炲拰-鈭炰箣鍒嗭紝涓涓+鈭炲拰涓涓-鈭炵殑鍜岋紝涓嶄竴瀹氭槸鏃犵┓澶э紝鍙兘鏄棤绌峰ぇ锛屼篃鍙兘鏄棤绌峰皬锛屼篃鍙兘鏄换浣曟湁闄愬父鏁帮紝涔熸湁鍙兘鏃鏋侀檺銆傛棤绌峰皬閲忓嵆浠ユ暟0涓烘瀬闄愮殑鍙橀噺锛屾棤闄愭帴杩戜簬0銆傜‘鍒...
