sin5度sin25度-cos5度sin65度的值是多少
sin5sin25－sin95sin65=sin5cos65－sin85sin65
=sin5cos65－cos5sin65
=sin(5-65)
=sin(-60)
=-sin60
=-√3/2
绛旓細sin5sin25锛峴in95sin65 =sin5cos65锛峴in85sin65 =sin5cos65锛cos5sin65 =sin(5-65)=sin(-60)=-sin60 =-鈭3/2
绛旓細sin5sin25锛峴in95sin65 =sin5cos65锛峴in85sin65 =sin5cos65锛cos5sin65 =sin(5-65)=sin(-60)=-sin60 =-鈭3/2
绛旓細sin 25搴锝0.4226 姝ｅ鸡sinA=鈭燗鐨勫杈/鏂滆竟锛屽彲浠ョ畝鍗曡鎴愭寮in=瀵硅竟姣旀枩杈广傛寮︾殑鎹㈢畻鏄寚灏嗚搴︽垨寮у害杞崲涓哄搴旂殑姝ｅ鸡鍊笺傚湪涓夎鍑芥暟涓紝姝ｅ鸡锛坰ine锛夋槸涓涓潪甯搁噸瑕佺殑鍑芥暟锛屽畠鎻忚堪浜嗗湪鐩磋涓夎褰腑瀵硅竟涓庢枩杈圭殑姣斿笺傛寮︾殑鍗曚綅鏄姬搴︼紙radians锛夛紝鍏跺畾涔夋槸寮ч暱涓庡崐寰勪箣姣斻傚洜姝わ紝鍦ㄨ繘琛屾寮...
绛旓細=-cos(95搴+25搴)=-cos120搴 =1/2
绛旓細涓銆sin搴︽暟鍏紡 1銆乻in 30= 1/2 2銆乻in 45=鏍瑰彿2/2 3銆乻in 60= 鏍瑰彿3/2 浜屻cos搴︽暟鍏紡 1銆乧os 30=鏍瑰彿3/2 2銆乧os 45=鏍瑰彿2/2 3銆乧os 60=1/2涓夈乼an搴︽暟鍏紡 1銆乼an 30=鏍瑰彿3/3 2銆乼an 45=1 3銆乼an 60=鏍瑰彿3
绛旓細=鏍瑰彿2脳(鏍瑰彿2)/2脳(sin15搴-cos15搴)=鏍瑰彿2脳[sin15搴γ(鏍瑰彿2)/2-cos15搴γ(鏍瑰彿2)/2]=鏍瑰彿2脳[sin15搴γ梒os45搴-cos15搴γ梥in45搴=鏍瑰彿2脳sin(15掳-45掳)=鏍瑰彿2脳sin(-30掳)=鏍瑰彿2脳(-1/2)=-(鏍瑰彿2)/2 甯屾湜瀵规偍鏈夋墍甯姪 濡傛湁闂锛屽彲浠ヨ拷闂傝阿璋㈡偍鐨勯噰绾 ...
绛旓細cos锛宻in锛宼an鐨勫叧绯诲涓嬶細姝ｅ鸡sin=瀵硅竟姣旀枩杈广備綑寮os=閭昏竟姣旀枩杈广傛鍒噒an=瀵硅竟姣旈偦杈广備笁瑙掑嚱鏁sincostan瀵瑰簲鐨勫叕寮忥細sin30掳=1/2sin45掳=鈭2/2sin60掳=鈭3/2sin90掳=1銆俿in蟺/6=1/2sin蟺/4=鈭2/2sin蟺/3=鈭3/2sin蟺/2=1銆俢os30掳=鈭3/2cos45掳=鈭2/2cos60掳=1/2cos90...
绛旓細cos(50掳+25掳)=cos50掳cos25掳- sin50掳sin25掳=(2cos²25掳-1)cos25掳 -2sin²25cos25掳=2cos³25掳-cos25掳 -2cos25掳(1-cos²25)=4cos³25掳-3cos25掳=(鈭6-鈭2)/4 鍒╃敤鍗′腹鍏紡鍗冲彲瑙ｅ緱cos25掳銆傚悓瑙掍笁瑙掑嚱鏁扮殑鍩烘湰鍏崇郴寮 鍊掓暟鍏崇郴锛歵an伪 路...
绛旓細sin50掳sin25掳=(2cos²25掳-1)cos25掳 -2sin²25cos25掳=2cos³25掳-cos25掳 -2cos25掳(1-cos²25)=4cos³25掳-3cos25掳=(鈭6-鈭2)/4 鍒╃敤鍗′腹鍏紡鍗冲彲瑙ｅ緱cos25掳銆備负鏂圭▼(1)鐨勫垽鍒紡銆傚綋D>0鏃讹紝鏂圭▼(1)鏈変笁涓袱涓や笉鍚岀殑瀹炴牴锛岀О涓轰笉鍙害鎯呭舰...
绛旓細sin25搴27鍒=cos(64搴33鍒)
