已知x属于(0,2/派)sinx+cosx+=1/2,则sinx乘以cosx=?sinx-cosx=? 零到二分之派
sinx+cosx=1/2平方得:1+2sinxcosx=1/4
sinxcosx=-3/8
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绛旓細瑙o細鍦╢(x^2)涓紝0<=x<=2,0 <=x^2<=4,鎵浠ワ紝鍦╢(x)涓紝0<=x<=4,f(x)鐨勫畾涔夊煙涓篬0,4].娉ㄦ剰 锛氬湪f(x)涓殑x鐩稿浜巉(x^2)涓殑x^2
绛旓細褰x灞炰簬锛0,蟺/2锛夋椂,2x+蟺/6灞炰簬锛埾/6,7蟺/6锛夋晠褰2x+蟺/6=蟺/2 x=蟺/6鏃,f锛坸锛夋湁鏈澶у 鏁2+a=4 a=2
绛旓細绠鍗曡绠椾竴涓嬪嵆鍙紝绛旀濡傚浘鎵绀
绛旓細鏉′欢閭i儴鍒嗗簲璇ユ槸涓斿浠绘剰x鈭圧閮芥湁f(2+x)=f(2-x).浣犳病鏈夋墦鍏ㄦ槸鍚鈭圼0,2]鏃,f(x)=3x+2f(x)鏄伓鍑芥暟鍒檉(-x)=f(x)x鈭圼-2,0]鏃秄(x)=3x+2浠鈭圼-4,0]鍒2+x鈭圼-2,2]浜庢槸f(2+x)锛3x+2浠2+x锛漷x锛漷-2f(t)锛3锛坱-2锛+2 锛3t-4鎵浠鈭圼-4,0]鏃秄(x)锛...
绛旓細鍏堟眰f锛坸锛夊畾涔夊煙锛屽啀姹俧锛坸+1锛夊畾涔夊煙
绛旓細鍥炵瓟锛(1)4x^2-12x^2-3=(2x+1)^2-8(2x+1)+4,鎵浠=4,褰2x+1灞炰簬(0,2],鍗x灞炰簬(-1/2,1/2]鏃,鏄噺鍑芥暟,褰2x+1灞炰簬[2,鈥)鏃,鍗硏灞炰簬[1/2,鈥)鏃,鏄鍑芥暟銆傚張鐢变簬宸茬煡x灞炰簬[0,1],鏁呰鍑芥暟鍗曡皟鍑忓尯闂翠负[0,1/2],鍗曡皟澧炲尯闂翠负[1/2,2]銆傛渶澶у间负f(1/2)=-1...
绛旓細瑙o細璁緁(x)=x²-ax+2=(x-a/2)²-a²/4+2锛坸>0锛夊垯 f(x)鍥惧儚鏄紑鍙e悜涓婂緱鎶涚墿绾匡紝瀵圭О杞存槸x=a/2銆傦紙1锛夎嫢瀵圭О杞村湪y杞村強鍏跺乏渚э紝姝ゆ椂a/2鈮0鍗砤鈮0 姝ゆ椂闇淇濊瘉f(0)鈮0锛鑰宖(0)=2>0,鎵浠ュ綋a鈮0鎴愮珛 锛2锛夊绉拌酱鍦▂杞村彸渚э紝姝ゆ椂a/2>0鍗砤>0 姝ゆ椂闇淇濊瘉f...
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绛旓細f(x)=(x+a)e^x f(x)=e^x+(x+a)e^x=(x+a)e^x 椹荤偣x=-a x<-a,f'(x)<0,f(x)鍗曡皟閫掑噺 x>-a,f'(x)>0,f(x)鍗曡皟閫掑 f(-a)=0鏄瀬灏忓 褰揳>0,x鈭圼0,2]鍖洪棿鍦ㄩ┗鐐箈=-a鍙充晶 f(x)鍗曡皟閫掑 f(x)鈮(0)=a鈮²鈫抋鈮²褰-2鈮鈮0,x鈭圼0,2...