If t is a positive integer and r is the remainder when t^2 + 5t + 6 is divided by 7, what is the value of r ?
(1) When t is divided by 7, the remainder is 6.
(2) When t2 is divided by 7, the remainder is 1.
ANS: A
錯誤的選到了 E
我先用因式分解之下得 (t+2)(t+3)=0,可是還是找不出答案,選到了E
請問這題應該要從那邊開始「下手」
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