given the function y=5x^3+16x^2-8x+7
1.find dy over dx and d^2y over dx^2
2.determine all the turning point(s)
3.Identify the nature of the turning point(s) found ib (2,) whether is a maximum
point or minimum point by second derivative test
differentiation
2010-06-03 10:01 pm
回答 (3)
2010-06-04 4:51 am
✔ 最佳答案
1. y' = 15x^2 +32x-8y"= 30x+32
2. Point of inflextion : (-16/15 , 18677/675)
Turning pts: (0.226,6.067) & (-2.359,49.272)
3. When x = 0.226 y">0 , so when x=0.226 it attains minimum
When x =-2.359 y"<0 , so when x=-2.359 it attains maximum
p.s. y' = dy/dx , y" = dy' /dx
2010-06-04 21:49:15 補充：
Turning points 既揾法系將 y' equate 做0 solve 個x 至於 系max 定 min 就sub 佢落y" ,
>0 就系 min, <0就系max . Point of inflextion 就系equate y"做0 solve 個x.
2010-06-04 7:15 am
that's great, but I also want the steps
2010-06-03 10:24 pm
1)dy over dx=15x^2+32x-8
d^2y over dx^2=30x=32
d^2y over dx^2=30x=32
收錄日期: 2021-04-13 17:17:28
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