[微分] 極值問題
2/3
f(x)= x (2x+5) ,find (i) extreme , (ii) inflection , (iii) increasing
and decreasing interval , (iv) concave upward and concave outward.
先附上我的作法
10x+10
f'(x) = --------- ---> f'(x) = 0 or not exist
1/3
3(x)
x = -1 and x = 0 (critical point)
20x-10
f''(x) = --------- --- > f''(x) = 0 or not exist
4/3
9(x)
x = 1/2 and x= 0 (critical point)
x -1 0 1/2
f (x) - 0 +
f '(x) + 0 - no +
f''(x) - no 0 +
我想請問 0 那點要怎麼判斷阿
弄進去是沒有值 一二階導函數不存在
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◆ From: 114.34.122.244
推
06/30 22:17, , 1F
06/30 22:17, 1F
→
06/30 22:19, , 2F
06/30 22:19, 2F
推
06/30 22:26, , 3F
06/30 22:26, 3F
→
07/01 01:35, , 4F
07/01 01:35, 4F
還是只要單就 critical point 兩側去判斷它的性質即可?
※ 編輯: sagu 來自: 114.34.122.244 (07/01 13:03)
推
07/01 13:39, , 5F
07/01 13:39, 5F
討論串 (同標題文章)