問題詳情
7. 若二次函數y＝x2＋ax＋b的圖形與x軸交於(－3 , 0 )、( 7 , 0 )兩點，則其對稱軸方程式為何？
(A) x＋2＝0
(B) x－2＝0
(C) x＋3＝0
(D) x－7＝0
(A) x＋2＝0
(B) x－2＝0
(C) x＋3＝0
(D) x－7＝0
參考答案
答案：B
難度：計算中-1
書單：沒有書單，新增
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