f（x+2）是偶函数，则它的对称轴是多少，是x= f(x+2)是偶函数，则它的对称轴是多少，是x=-2还是x=...
\u82e5\u51fd\u6570f(x+2)\u662f\u5076\u51fd\u6570\uff0c\u90a3\u4e48\u5b83\u7684\u5bf9\u79f0\u8f74\u5e94\u8be5\u662f\u591a\u5c11\u4e3a\u53d9\u8ff0\u65b9\u4fbf\uff0c\u628ax+2\u770b\u505a\u4e00\u4e2a\u6574\u4f53\uff0c\u53ef\u4ee5\u8bbe
x+2=t\uff0c\u5219x=t-2.
\u2235f(x+2)\u662f\u5076\u51fd\u6570\uff0c
\u2234f(t)=f(-t)\uff0c\u4e14\u56fe\u8c61\u5173\u4e8et=0\u5bf9\u79f0\uff0c
\u2234\u56fe\u8c61\u5173\u4e8ex+2=0\u5373x=-2\u5bf9\u79f0\u3002
\u4f60\u8ba4\u4e3a\u7684f(x+2)=f(-x-2),\u662f\u5bf9\u51fd\u6570\u7684\u7406\u89e3\u6709\u8bef\u3002
\u6309\u7167\u5076\u51fd\u6570\u7684\u5b9a\u4e49\uff0c\u628a\u51fd\u6570\u7684\u81ea\u53d8\u91cf\u6362\u6210\u5176\u76f8\u53cd\u6570\u51fd\u6570\u503c\u4e0d\u53d8\uff0c\u51fd\u6570\u5c31\u662f\u5076\u51fd\u6570\u3002
f(x+2)\u7684\u81ea\u53d8\u91cf\u662fx\uff0c\u800c\u4e0d\u662fx+2\uff0c
\u56e0\u6b64f(x+2)\u662f\u5076\u51fd\u6570\uff0c\u53ea\u80fd\u628ax\u6362\u4e3a-x\u5f97
f(-x+2)=f(x+2)\uff08\u539f\u51fd\u6570\uff09\uff0c\u5e76\u975ef(x+2)=f(-x-2)\u3002
\u662fx=-2.\u56e0\u4e3a\u5982\u679cf(x)\u662f\u5076\u51fd\u6570\uff0c\u5219\u5bf9\u79f0\u8f74\u662fx=0,\u90a3\u4e48f(x+2)\u662f\u5076\u51fd\u6570\uff0c\u5219\u5b83\u7684\u5bf9\u79f0\u8f74\u662fx+2=0,\u6240 \u4ee5x=-2.
f(x+2)的对称轴就是x=0f(x)的对称轴是x=2.因为f(x)相当于f(x+2)向右平移2个单位（左加右减）
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绛旓細鑷充簬浣犺拷闂噷闈㈢殑锛岃櫧鐒朵綘鏄护t=x+2浜嗭紝浣f锛坸+2锛涓鍋跺嚱鏁帮紝鏄互x涓鸿嚜鍙橀噺锛岃屼笉鏄痶涓鸿嚜鍙橀噺锛屾墍浠锛坱锛夊苟涓嶇瓑浜巉锛-t锛夛紝涔熷嵆f锛坱锛夌殑瀵圭О杞村苟涓嶆槸t=0锛岃屾槸x=0鏃秚鐨勫彇鍊硷紝姝ゆ椂t=0+2=2锛屼篃鍗砯锛坱锛夌殑瀵圭О杞翠负t=2銆傚嚱鏁颁腑锛屽洜涓鸿嚜鍙橀噺t鍜寈鐨勫彇鍊艰寖鍥存槸涓鑷寸殑锛屽嵆瀵瑰嚱鏁癴锛坱...
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绛旓細杩愮畻娉曞垯 (1) 涓や釜鍋跺嚱鏁鐩稿姞鎵寰楃殑鍜屼负鍋跺嚱鏁般(2) 涓や釜濂囧嚱鏁扮浉鍔犳墍寰楃殑鍜屼负濂囧嚱鏁般(3) 涓涓伓鍑芥暟涓庝竴涓鍑芥暟鐩稿姞鎵寰楃殑鍜屼负闈炲鍑芥暟涓庨潪鍋跺嚱鏁般(4) 涓や釜鍋跺嚱鏁扮浉涔樻墍寰楃殑绉负鍋跺嚱鏁般(5) 涓や釜濂囧嚱鏁扮浉涔樻墍寰楃殑绉负鍋跺嚱鏁般(6) 涓涓伓鍑芥暟涓庝竴涓鍑芥暟鐩镐箻鎵寰楃殑绉负濂囧嚱鏁般
