Question

Graphing Question!

Answer 1

\[a=\sqrt{5}\]

Answer 2

apparently that's not right =/

Answer 3

ah true. doesn't fulfill conditions

Answer 4

@Luigi0210 help please?

Answer 5

@Jhannybean she's got you

Answer 6

The original graph of f(x) is graph A, and graph B is f ' (x)

you're given

f(x) = x^2 ( x - 15 )

in order to find where the original function is increasing and decreasing, you have to find the derivative of the function. f ' (x) . Have you found that yet?

Answer 7

3(x-10)x ?

Answer 8

f ' * (g) + g ' * ( f )

right? Product rule.

Answer 9

2x(x-15)+(x^2)

Answer 10

it's easier than product rule. open brackets. and result is 3 (-10+x) x

in final calculations a is sqrt8

Answer 11

sqrt8 is wrong =/

Answer 12

how are you getting 3 ( x - 10) ?

Answer 13

Oh I gotcha.

Answer 14

opening brackets of original function before derivating.

Answer 15

f ' (x) = 2x(x - 15) + x^2 = 0

f ' (x) = 2x^2 - 30x + x^2 = 0

f ' (x) = 3x^2 - 30x = 0

f ' (x) = 3x( x - 10 ) = 0

solve for x values, they'll give you the critical points.

Answer 16

oo kk 10 is the answer - thanks so much!

Answer 17

haha true 10 ! so simple.

Answer 18

Do you know how to test them though? test the numbers in between these two points by taking numbers before and after 0, and before and after 10 and put them into your original function to get a positive or negative value.

Answer 19

I'm kind of having doubts but okay

Answer 20

yeah that's how I got it - I know what to do from there - just didn't know how to start it off

Answer 21

doubts about?

Answer 22

Nothing ^_^'