(1-cosx)/sinx 还能再怎么化简 sinx/1-cosx应该怎么继续分解?
sinx/(1-cosx)\u600e\u4e48\u5316\u7b80
\u7b54\uff1a\u4e8c\u500d\u89d2\u516c\u5f0f\uff1asin2a=2sinacosa\uff0ccos2a=2cos²a-1=1-2sin²asinx/(1-cosx)=2sin(x/2)cos(x/2)/[2sin²(x/2)]=cot(x/2)
sinx/1\uff0dcosx
\uff1dsinx\uff081\uff0bcosx\uff09/\uff081\u4e00cosx\uff09\uff081\uff0bcosx\uff09
\uff1dsinx\uff081\uff0bcosx\uff09/\uff081\u4e00cos²x\uff09
\uff1dsinx\uff081\uff0bcosx\uff09/sin²x
\uff1d\uff081\uff0bcosx\uff09/sinx
1-(1-2sinx的平方))/2sinxcosx=2sinx的平方/2sinxcosx=sinx/cosx=tanx
注:我这里的X是你原题上X的一半,也就是半角
(1-cosx)/sinx
=sinx(1-cosx)/sin²x
=sinx(1-cosx)/(1-cos²x)
=sinx(1-cosx)/(1+cosx)(1-cosx)
=sinx/(1+cosx)
=2sin(x/2)cos(x/2)/2cos²(x/2)
=sin(x/2)/cos(x/2)
=tan(x/2)
(1-cosx)/sinx =[1-(1-2·cosx/2^2)]/(2·sinx/2·cosx/2)=2·cosx/2^2/(2·sinx/2·cosx/2)=cosx/2/sinx/2=ctgx/2
tanx/2
绛旓細涓嶈兘鐢ㄦ媺鏍兼湕鏃ヤ腑鍊煎畾鐞嗐傝繖棰樹笉鑳界敤鎷夋牸鏈楁棩涓煎畾鐞,鍥犱负鎷嗘垚[cos(sinx)-cosx]/(sinx-x)*(sinx-x)/(1-cosx)sinx涔嬪緦,鍒嗗埆璁$畻姣忛」鏋侀檺.绗竴椤圭敤鎷夋牸鏈楁棩涓煎畾鐞嗗緱鏋侀檺鏄0,鑰岀浜岄」鐢ㄧ瓑浠锋棤绌峰皬鏇挎崲寰楁瀬闄愭槸鈭,鎵浠ヤ笉鑳藉埄鐢ㄧН鐨勬瀬闄愮瓑鏂兼瀬闄愮殑绉潵鎷嗗紑.
绛旓細澶归煎噯鍒欑殑璇,浣犺鍖栫畝涓嬪晩 1 - cosX = 2sin(X/2)^2 寰堟槑鏄2 sin(X/2)^2 > 0 鑰屼笖,鍦 [0,蟺/2] 涓,cos鏄皬浜1澶т簬0鐨,鏁, sin(X/2)^2 < sin(X/2)鎵浠 2sin(X/2)^2 < 2 sin(X/2)鍗 0 < 1 - cosX < 2 sin(X/2)2sin(X/2)瓒嬩簬0,鎵浠1 - cosX 瓒嬩簬0.....
绛旓細浣犺繖鏍峰仛鏄笉琛岀殑銆
绛旓細瑙佸浘鐨勫垎鏋
绛旓細1-acosx鐨勭瓑浠锋棤绌峰皬鏄紙ax锛塣2/2銆傚師寮=1-cos锛ax锛=2[sin锛坅x/2锛塢^2~2*锛坅x/2锛塣2=锛坅x锛塣2/2銆傚湪鍚屼竴鑷彉閲忕殑瓒嬪悜杩囩▼涓紝鑻ヤ袱涓棤绌峰皬涔嬫瘮鐨勬瀬闄愪负1锛屽垯绉拌繖涓や釜鏃犵┓灏忔槸绛変环鐨勩傛棤绌峰皬绛変环鍏崇郴鍒荤敾鐨勬槸涓や釜鏃犵┓灏忚秼鍚戜簬闆剁殑閫熷害鏄浉绛夌殑銆傜瓑浠锋棤绌峰皬鏇挎崲鏄绠楁湭瀹氬瀷鏋侀檺鐨...
绛旓細绠鍗曞垎鏋愪竴涓嬪嵆鍙紝璇︽儏濡傚浘鎵绀
绛旓細鐩存帴姹傛瀬闄 lim x鈫0 (1-cosx)/x 鍙互鐩存帴娲涘繀杈炬硶鍒 =lim sinx/1 =0 鎴栬呯瓑浠锋棤绌峰皬1-cosx~x²/2 =lim x²/2/x =lim x/2 =0 缁撴灉閮戒负0 璇存槑1-cosx鏄痻鐨勯珮闃舵棤绌峰皬
绛旓細r=a(1-cosx)鐨勬瀬鍧愭爣鍥惧儚鏄績褰㈢嚎銆傚績褰㈢嚎锛屾槸涓涓渾涓婄殑鍥哄畾涓鐐瑰湪瀹冪粫鐫涓庡叾鐩稿垏涓斿崐寰勭浉鍚岀殑鍙﹀涓涓渾鍛ㄦ粴鍔ㄦ椂鎵褰㈡垚鐨勮建杩癸紝鍥犲叾褰㈢姸鍍忓績褰㈣屽緱鍚嶃傛瀬鍧愭爣鏂圭▼ 姘村钩鏂瑰悜锛 蟻=a(1-cos胃) 鎴 蟻=a(1+cos胃) (a>0)鍨傜洿鏂瑰悜锛 蟻=a(1-sin胃) 鎴 蟻=a(1+sin胃) (a>0)...
绛旓細鐢ㄤ簡娉板嫆鍏紡锛屽畠鍙互鎶婁竴浜涘鏉傜殑鍑芥暟閫艰繎杩戜技鍦拌〃绀轰负绠鍗曠殑澶氶」寮忓嚱鏁般備緥锛cosx=1-x^2/2锛+x^4/4锛佲︹
绛旓細r=a锛1-cosx锛鐨勬瀬鍧愭爣鍥惧儚鏄竴涓績褰㈢嚎锛屽鍥炬墍绀恒傛槸涓涓渾涓婄殑鍥哄畾涓鐐瑰湪瀹冪粫鐫涓庡叾鐩稿垏涓斿崐寰勭浉鍚岀殑鍙﹀涓涓渾鍛ㄦ粴鍔ㄦ椂鎵褰㈡垚鐨勮建杩癸紝鍥犲叾褰㈢姸鍍忓績褰㈣屽緱鍚嶃傚績褰㈢嚎鍦ㄤ笉鍚屾柟鍚戞湁涓嶅悓鐨勬瀬鍧愭爣琛ㄨ揪寮忥細姘村钩鏂瑰悜锛歳=a锛1-cos胃锛夋垨 r=a锛1+cos胃锛夛紙a>0锛夛紱鍨傜洿鏂瑰悜锛歳=a锛1-sin胃锛夋垨...