（初二数学）为什么函数图像直线平移是左加右减呢？ 在数学坐标轴上是左减右加,而为什么在函数图像平移却是左加右减
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左加右减，上加下减
绛旓細鍥犱负涓姝ｄ竴璐熷晩
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绛旓細y=0鏃讹紝0=-2x+6 x=3 鍥捐薄涓鸿繛鎺(0,6)鍜(3,0)鐨鐩寸嚎锛泍=3x-4...(2)x=0鏃讹紝y=3*0-4=-4 x=1鏃讹紝y=3*1-4=-1 鍥捐薄涓鸿繛鎺(0,-4)鍜(1,-1)鐨勭洿绾裤(2) 鑱旇В(1)(2)锛屽緱鍒颁袱鐩寸嚎鐨勪氦鐐癸細(2,2)(3) 褰搙<2鏃讹紝y=-2x+6鐨勫浘璞鍦▂=3x-4鐨勪笂鏂广
绛旓細瑙:鎴戜滑鐭ラ亾.涓娆鍑芥暟鐨鍥惧儚鏄竴鏉鐩寸嚎.鍥犱负璇ョ洿绾縴=4x-3鐩镐氦浜巟杞翠笂鐨勪竴鐐.浠=0.寰梮=3/4.鎵浠ユ墍姹傜洿绾夸篃缁忚繃鐐(3/4.0).缁忚繃涓ょ偣(3.-3).(3/4.0).姹傜洿绾挎柟绋嬬殑鏂规硶鏈夊緢澶.杩欓噷浣犲彲浠ヨy=kx+b.鍒嗗埆灏嗕袱鐐瑰潗鏍囦唬鍏.鏈鍚庢眰寰梜=-4/3.b=1.鎵浠ョ洿绾挎柟绋嬩负y=-(4/3)x+1.鍗虫墍姹...
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绛旓細鍥炵瓟锛氬厛鐢诲嚭骞抽潰鐩磋鍧愭爣绯,鐒跺悗鍒嗗埆璁緓绛変簬0鍜1,鍐嶅垎鍒畻鍑鸿繖鏄痽绛変簬鍑犮備篃灏辨槸褰搙=0,y=-1,褰搙=1,y=3涔熷氨鏄杩欎釜鍥惧儚杩(0,-1)鍜(1,3)杩欎袱涓偣,鍦ㄥ钩闈㈢洿瑙掑潗鏍囩郴涓壘鍒拌繖涓や釜鐐瑰苟杩炴帴鍗冲彲銆愮函鎵嬫墦,鏈涢噰绾炽
