Question

CAN SOMEONE PLEASE EXPLAIN THIS?!?!
Find the derivative of f(x) =-9/x at x = 6.

Answer 1

Are you familiar with the power rule?

Answer 2

No I don't understand any of this I just want to finish this class so I can graduate.... @jim_thompson5910

Answer 3

is this for calculus class or another kind of class?

Answer 4

it's pre-calc @jim_thompson5910

Answer 5

ok you can type in "derivative of f(x) =-9/x" into wolfram alpha to get

https://www.wolframalpha.com/input/?i=derivative+of+f%28x%29+%3D-9%2Fx

what does it say for f ' (x) ?

Answer 6

are you talking about the 9/x^2 or the 9?

Answer 7

yes 9/x^2

Answer 8

ok

Answer 9

\[\Large f \ ' (x) = \frac{9}{x^2}\]

\[\Large f \ ' (6) = \ ??\]

Answer 10

sorry i lost connection i'm back now! was it 9/36??

Answer 11

@jim_thompson5910

Answer 12

yes, now reduce

Answer 13

1/4?

Answer 14

yep

Answer 15

yay! i have one more, can you help me?

Answer 16

sure

Answer 17

its a short response question;
The position of an object at time t is given by s(t) = -8 - 9t. Find the instantaneous velocity at t = 1 by finding the derivative.

Answer 18

you can use wolfram alpha to compute the derivative function

Answer 19

it's unfair how they are asking you derivative questions in a pre-calc class

Answer 20

i'm in the last chapter so idk

Answer 21

what is s ' (t) ?

Answer 22

to be completely honest i don't know...

Answer 23

what do you get when you type in "derivative of s(t) = -8 - 9t" into wolfram

Answer 24

-9 :)

Answer 25

yep, in this case the derivative is the same no matter what t is

Answer 26

basically the rate of change is the same throughout

Answer 27

alright so to get credit for the short essay what else do i need to put??

Answer 28

you can throw in how it's a linear equation which has the same slope throughout

Answer 29

slope of linear equation = rate of change

Answer 30

it's a linear equation so the rate or change remains the same, which is -9??

Answer 31

how does that sound?

Answer 32

that sounds good

Answer 33

oh it's "rate OF change" not rate or change

Answer 34

okay thanks!! :D You've been a great help!!!

Answer 35

np

Answer 36

oh typo!! X)