Page 131 - 《數學觀念總整理 3-4 》- 2019版
P. 131
3
2 + 3 = 5 ∆ 6 27
ex ∶ 3 + 6 = 1 ⟹ = ∆ = 2 3 = 3 = 9 ⟹ 唯一解
3 6
係數不成比例 (Δ ≠ 0 ),代表兩條線不平行,代表兩線交於一點
3
2 + 3 = 5 ∆ 6 9
ex ∶ 4 + 6 = 7 ⟹ = ∆ = 2 3 = 0 ⟹ 0 ∙ = 9 ⟹ 無解
4 6
10
係數成比例 (Δ = 0 ),但常數項不成比例 (Δ ≠ 0 ),代表兩線平行
3
2 + 3 = 5 ∆ 6 0
ex ∶ 4 + 6 = 10 ⟹ = ∆ = 2 3 = 0 ⟹ 0 ∙ = 0 ⟹ 無限多解
4 6
= 3 + 1
⟹ 2 + 3y = 5 ⟶ 參數式 ∶
= −2 + 1
係數成比例 (Δ = 0 ),且常數項也成比例 (Δ = 0 ),代表兩線重合
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