cos(x-½)，x趋于正无穷是等于多少
cos\uff08x+y\uff09\u7b49\u4e8e\u5565\u6765\u7740?cos\uff08x+y\uff09=cosxcosy-sinxsiny
=cos(-\u03c0/2+x/2)=sin(x/2)
\u4f60\u786e\u5b9a\u4f60\u7684\u7b54\u6848\u662f\u5bf9\u7684\u5417\uff1f \u6211\u8ba4\u4e3a\u4f60\u7684\u7b54\u6848\u9519\u4e86
cos(\u03c0/2-x/2)=cos(-\u03c0/2+x/2)\uff0c\u4f60\u628aX/2\u770b\u6210\u4e2a\u6574\u4f53\uff0c\u770b\u56fe\u8c61\u5c31\u77e5\u9053COS\uff08T-\u03c0/2\uff09\u4e0d\u7b49\u4e8eCOST
\u6211\u8bf4\u628a\u770b\u6210\u6574\u4f53\u662f\u7528\u4e86\u56fe\u8c61\u6cd5\uff0cCOSX\u5411\u53f3\u5e73\u79fb\u03c0/2\u4e0d\u5c31\u662fSINX\u5417
绛旓細cos锛-x锛夌殑璐熷彿涓嶈兘鎻愬嚭鏉ャ傛牴鎹笁瑙掑嚱鏁扮殑鎬ц川锛宑os鍑芥暟鍏锋湁鍋跺嚱鏁扮殑鎬ц川锛屽嵆cos锛-x锛 = cos锛坸锛夈傝繖鏄洜涓轰綑寮﹀嚱鏁板湪鍗曚綅鍦嗕笂鐨勫畾涔夋槸閫氳繃姘村钩杞寸殑鎶曞奖寰楀埌鐨勶紝鑰岃礋瑙掑害琛ㄧず鐨勬槸閫嗘椂閽堟棆杞紝鎵浠os锛-x锛夊拰cos锛坸锛夌殑鍊兼槸鐩稿悓鐨勩傚洜姝わ紝cos锛-x锛夌殑璐熷彿涓嶈兘鐩存帴鎻愬嚭鏉ワ紝浣嗘槸cos锛-x锛...
绛旓細瑙ｇ敱f(x)=cos(x-3)寰梖(-x)=cos(-x-3)=cos(x+3)鍗砯(-x)鈮犅眆(x)鏁協(x)=cos(x-3)鏄潪濂囬潪鍋跺嚱鏁般
绛旓細 cos(-x)鏄寚瑙掑害涓-x鐨勪綑寮﹀笺備綑寮﹀嚱鏁版槸涓涓懆鏈熸у嚱鏁帮紝鍛ㄦ湡涓2蟺锛屽洜姝os(-x)鍙互鍐欐垚cos(-x+2蟺)鐨勫舰寮忋傛垜浠煡閬揷os鍑芥暟鏄伓鍑芥暟锛屽嵆cos(x)=cos(-x)锛屽洜姝os(-x)=cos(x)銆傛墍浠os(-x)鍜宑os(x)鍦ㄦ暟鍊间笂鏄浉绛夌殑锛岄兘浠ｈ〃浜嗚搴︿负x鐨勪綑寮﹀笺 涓...
绛旓細涓ょ鎺ㄥ杩囩▼瑙ｇ瓟杩欎釜闂锛氾紙1锛夋垜浠彲浠ョ敤涓夎鍑芥暟宸殑鍏紡姹傝В杩欎釜闂 cos(锛峹)= cos(0-x)= cos0cosx+sin0sinx = cosx 锛2锛夊悓鏃朵篃鍙互鐢ㄤ笁瑙掑嚱鏁扮嚎鐩磋鍦扮悊瑙 鍋囪x鏄竴涓瑙掞紝閭ｄ箞瀹冪殑璐熻-x涓庝箣鍏充簬X杞村绉帮紙绗洓璞￠檺锛夛紝鍥犳cos(-x)鏄疧A/R锛岃岄潪-OA/R....
绛旓細cosx鏄伓鍑芥暟锛屾墍浠cos(-x)=cosx銆傜敾涓涓崟浣嶅渾锛屼綔涓や釜瑙掞細涓涓獂锛屼竴涓-x銆傚彲浠ョ湅鍑猴細cosx=OA/R銆傝宑os(-x)=OA/R銆傚洜姝わ細 cos(-x) = cosx銆傝鍥撅細浣欏鸡骞抽潰鍑犱綍璇佹硶 鍦ㄤ换鎰忊柍ABC涓紝鍋欰D鈯C锛屼氦BC浜嶥锛屸垹C鎵瀵圭殑杈逛负c锛屸垹B鎵瀵圭殑杈逛负b锛屸垹A鎵瀵圭殑杈逛负a銆傚垯鏈夛細BD=c*cosB锛...
绛旓細璺cos(x)鐨勫浘鍍忔槸涓鏍风殑锛屽洜涓篶os(x)鏄伓鍑芥暟
绛旓細鏈灏忔鍛ㄦ湡 瑙ｉ杩囩▼濡備笅鍥撅細
绛旓細瑙ｏ細y=cos (x-1)杩欎釜鍑芥暟鏈澶у兼槸+1 鏈灏忓兼槸-1 鍛ㄦ湡鏄2k蟺 鏈灏忔鍛ㄦ湡鏄2蟺
绛旓細鐢讳竴涓崟浣嶅渾 浣滀袱涓锛氫竴涓細x,涓涓-x 鍙互鐪嬪嚭锛cosx=OA/R 鑰 cos(-x)=OA/R 鍥犳锛 cos(-x) = cosx 瑙佸浘锛
绛旓細宸﹀姞鍙冲噺 鎵浠ュ悜宸1涓崟浣嶅垯鍚鏇挎崲涓簒+1 鎵浠ユ槸y=cos(x+1)+1 杩欎釜浣犺寰楀 鍙﹀,涓婂姞涓嬪噺鏄湪澶栭潰鐨 鍗砪os(x+1)+1鏁翠釜鍔犱笂1 鎵浠ユ槸cos(x+1)+2
