【正文】
y圖象上任一點,平移后函數(shù)a a a F P′ P F′ O P P′ a O xy 3lg?圖象上的對應(yīng)點為)( yxP ??? , 由平移公式得 ??? ??? ??? kyy hxx將它代入x3lg?得,與)(lg hxky ??? 3 1)23lg( ??? xy為同一函數(shù),?????????????????132123khkh 解得,故所求向量)( 132 ??? ,a 解法二:1323lg1)23lg( ??????? ?????? ????? xxy?即?????? ?????? ??? 323lg1 x 令???