lim1-cosb(b→∞)为什么不存在？ 极限limx→0+e?1xx=（ ）A．1B．0C．∞D．...
tan90\u5ea6\u4e3a\u4ec0\u4e48\u4e0d\u5b58\u5728\uff1f
\u56e0\u4e3atan\u03b8=sin\u03b8/cos\u03b8\uff0c
\u5f53\u03b8=90\u00b0\u65f6\uff0c\u5373tan90\u00b0=sin90\u00b0/cos90\u00b0=1/0\uff0c
\u56e0\u5206\u6bcd\u662f\u4e0d\u80fd\u4e3a0\u7684\uff0c\u6240\u4ee5\u4e0d\u5b58\u5728tan90\u00b0.
limx\u21920+e?1xx\uff1dlimt\u2192\u221etet\uff1dlimt\u2192\u221e1et\uff1d0\u5176\u4e2d\u4ee4t\uff1d1x\u6545\u9009\uff1aB\uff0e
cos函数的值是在-1到1之间而b趋于无穷大的时候
并不能确定cosb的极限值
因为其值并不固定，在-1到1之间波动
所以1-cosb的极限值也不存在
绛旓細=(lg1+e^0)/arccos0 =(0+1)/1 =1 2. 鍊掓暟娉,鍒嗘瘝鏋侀檺涓洪浂,鍒嗗瓙鏋侀檺涓轰笉绛変簬闆剁殑甯告暟鏃朵娇鐢. 銆愪緥3銆 lim[x-->1]x/(1-x) 鈭祃im[x-->1] (1-x)/x=0 鈭磍im[x-->1] x/(1-x)= 鈭 浠ュ悗鍑￠亣鍒嗘瘝鏋侀檺涓洪浂,鍒嗗瓙鏋侀檺涓轰笉绛変簬闆剁殑甯告暟鏃,鍙洿鎺ュ皢鍏舵瀬闄愬啓浣溾垶. 3....
绛旓細瑙ｏ細褰搙瓒嬪悜浜巃鏃讹紝鍒嗗瓙銆佸垎姣嶅潎瓒嬪悜浜0锛屾墍浠ユ牴鎹礇蹇呰揪娉曞垯锛屽鍒嗗瓙鍒嗘瘝鍒嗗埆姹傚寰 鏁呯瓟妗堜负锛歝os a
绛旓細涓鑸殑鏈甯哥敤鍏紡 鍙ｈ瘈;濂囧彉鍋朵笉鍙橈紝绗﹀彿鐪嬭薄闄 涓鑸殑鏈甯哥敤鍏紡鏈:Sin(A+B)=SinA*CosB+SinB*CosA Sin(A-B)=SinA*CosB-SinB*CosA Cos(A+B)=CosA*CosB-SinA*SinB Cos(A-B)=CosA*CosB+SinA*SinB銆俆an(A+B)=(TanA+TanB)/(1-TanA*TanB) Tan(A-B)=(TanA-TanB)/(1+TanA*TanB) ...
绛旓細C
绛旓細x瓒嬩簬0 lim sinax/tanbx=lim (sinax/ax )*(bx/sinbx) *cosbx *(a/b)=(a/b)lim sinax/ax * lim bx/sinbx *limcosbx =(a/b)*1*1*1 =a/b
绛旓細鍙互鐢ㄥ畾涔夋潵鍋氾紒寰垎锛屽疄璐ㄨ繕鏄瀬闄愩(sina)'=lim(b->0)[sin(a+b)-sina]/b 鍥犱负sin(a+b)=sinacosb+cosasinb 杩欓噷鐢ㄥ埌b鏃犵┓灏忥紝鎵浠ユ湁cosb=1.浜庢槸鏈塴im(b->0)[sin(a+b)-sina]/b =lim(b->0)[cosasinb]/b 鑰屽綋b鏃犵┓灏忥紝鏈塻inb/b=1.鎵浠ユ湁 lim(b->0)[sin(a+b)-sina]/b...
绛旓細lim(A+B)=limA+limB lim(A-B)=limA-limB lim(A脳B)=limA脳limB lim(A梅B)=limA梅limB(B鈮0)瀵兼暟鐨勫畾涔変负f'(x)=y'=lim(鈻硑/鈻硏)=lim{[f(x+鈻硏)-f(x)]/鈻硏} 鍏朵腑鈥渓im鈥(limit,鏋侀檺鐨勬剰鎬)绗﹀彿涓嬮潰鏄鍐欎笂鈥溾柍x瓒嬭繎浜0鈥濊繖涓笢涓滅殑锛屼负浜嗘墦瀛楄緭鍏ユ柟渚匡紝鎴戠粺涓缁欑渷鐣ヤ簡銆1...
绛旓細鍒╃敤瀵兼暟鐨勫畾涔夊彲浠ユ眰鍑虹粨鏋滐紝涔熷彲浠ョ洿鎺ュ埄鐢ㄥ鍚堝嚱鏁版眰瀵兼眰鍑虹粨鏋溿
绛旓細/n]]鐨勯暱搴︼紝鏈澶у尯闂撮暱搴ξ=max(xi)鈮^[(1+n)/n]-b^(n/n)=b[b^(1/n)-1]鈫0锛屼笖尉i=b^[(1+2i)/(2n)鈭圼b^(i/n)锛宐^[(1+i)/n]]锛屾弧瓒冲畾绉垎瀹氫箟鐨勬潯浠讹紝鈭村師寮=lim(n鈫掆垶)鈭憑b^[(1+i)/n]-b^(i/n)}sin[b^(2i+1)]=鈭(1,b)sinxdx=cos1-cosb ...
绛旓細渚2锛氭眰鏋侀檺lim3 x3x1 銆愯鏄庛戝瀷涓斿垎瀛愬垎姣嶉兘浠ュ椤瑰紡缁欏嚭鐨勬瀬闄,鍙氳繃鍒嗗瓙鍒嗘瘝鍚岄櫎鏉ユ眰銆11x3x21lim銆愯В銆憀im3 x3x1x33x3 銆愭敞銆(1) 涓鑸垎瀛愬垎姣嶅悓闄鐨勬渶楂樻鏂癸紱0nn1 axan1xa0 (2) limnmm1xbxbxbmm10an bn mnmn mn 3锛庡垎瀛(姣)鏈夌悊鍖栨眰鏋侀檺 渚3锛氭眰鏋侀檺lim(x23x21)x 銆...
