Question

Help please?

Answer 1

3 turning points, should be interesting!

Answer 2

I have no idea how to start it. Should I derive it first and then find the values?

Answer 3

I got 0 and -3

Answer 4

@mukushla was right, f'(x)=0 at the turning point

Answer 5

@DanJS

Answer 6

can you find \[\frac{ d }{ dx }f(x)\]

Answer 7

that expression will give you the slope of any tangent line to the curve at a point

Answer 8

When I derive it I got 6x^2+12x

Answer 9

You just have to remember,

\[\frac{ d }{ dx }[x^n]= n*x ^{n-1}\]

Answer 10

right, now set that slope expression to what they want, zero

Answer 11

horizontal line, zero slope

Answer 12

Dan the man!

Answer 13

(6x)(x+2) = 0

x can be 2 values , each quantity zero

Answer 14

Factors right?

Answer 15

6x=0
or
x+2=0

horizontal tangent line

Answer 16

use those x values in the original f(x) and find out each corresponding y value (x,y)

Answer 17

or nvermind, they dont want it

Answer 18

You get all 3 values Dan?

Answer 19

it is a cubic function , it turns around 2 times,

Answer 20

So it would be -2 and 0?

Answer 21

http://awesomescreenshot.com/0b9514fn7e

Answer 22

right

Answer 23

Take first derivative, set that expression to zero, solve for the values of x for each tangent line if they exist

Answer 24

Alright thank you so much!

Answer 25

np

Answer 26

as usual, well done @DanJS