Question

ANOTHER DIFFICULT ONE!...for me..

Let f(x)=X^2-100 . The average rate of change from x = -10 to x = 10 equals _____.

Answer 1

A. 100
B. 200
C. 0
D. -100

Answer 2

\[\LARGE ={f(10)-f(-10) \over 10-(-10)}\]

Answer 3

0?

Answer 4

yes

Answer 5

THANKS PAX!

Answer 6

imma fan :)

Answer 7

wouldn't that be undefined?

Answer 8

or we take a limit?

Answer 9

\[{0 \over 20} = 0\]

Answer 10

aaa ok

Answer 11

I was thinking something else

Answer 12

Let f(x)=1/x be the reciprocal function. The average rate of change from x = 0.01 to x = 0.1 equals _____.

Answer 13

do u guys think that this is -10

Answer 14

@PaxPolaris @timo86m ?

Answer 15

i believe its -10

Answer 16

its 0 I am with pax

Answer 17

no for the new question i just asked.

Answer 18

oh just follow pax's example

(f(xf)-f(xi))/ ( xf -xi )

Answer 19

so then its still 0 ?

Answer 20

o.O

Answer 21

\[\LARGE ={f(0.1)-f(.01) \over .1-(.01)}={-90 \over 0.09}=?\]

not -10

Answer 22

-1000!

Answer 23

I GUESS ITS ALL ABOUT HAVING THE RIGHT FUNCTION FOR EACH QUESTION, BUT ITS FIGURING OUT THAT FUNCTION THAT IS HARD.

Answer 24

-1000

Answer 25

what does it mean when it says the rate of change?

Answer 26

average rate of change is the SLOPE of the line passing through the two points
\[\LARGE ={y_2-y_1 \over x_2-x_1}\]

Answer 27

so dont you have to have cordinants to find that?

Answer 28

you have the x co-ords (eg -10 & 10 in the first question)

& you can calculate y=f(x)

Answer 29

because for another hard question i had it says f(x)=1/2x+5 then it states The average rate of change from x = 17 to x = 43 equals but didnt you say y2-y
1/x2-x1

Answer 30

all i have is the x cordinants

Answer 31

you have the equation to find y .... or f(x) if you prefer

Answer 32

ooo so y=1/2x+5

Answer 33

how do i get the y cordinants to look like the x cordinants
?

Answer 34

\[\LARGE ={f(43)-f(17) \over 43-17}\]

\[f(43) = {1 \over 2(43)+5}\]

Answer 35

1/91?

Answer 36

yes.. keep going ... find the final answer

Answer 37

ahh can u give me a hint on what to do next :(

Answer 38

whats f(17)

Answer 39

1/39

Answer 40

?

Answer 41

yes

Answer 42

i did read the equation right ? right? you meant :

\[\large f(x) = {1 \over 2x+ 5}\]

Answer 43

uhm f(x)=1/2 x <- the x is on the side of the fraction then +5