Question

i dont know how to find the derivative of absolutevalue(x-4)

Answer 1

it is 1 if x is bigger than 4, -1 if x is less than 4, and it is not differentiable at x = 4

Answer 2

that is because
\[f(x) = |x-4| = \left\{\begin{array}{rcc}
x + 4 & \text{if} & x \geq 4 \\
- x - 4& \text{if} & x < 4
\end{array}
\right.
\]

Answer 3

hah got to use "piecewise"

Answer 4

showoff

Answer 5

x-4 if x>4

Answer 6

stolen from zarkon(tm)

Answer 7

-(x-4)=-x+4 if x<4

Answer 8

actually just googled and got it, but zarkon put in the text

Answer 9

@myininaya i wrote it correctly. oh yes!

Answer 10

\[f(x) = |x-4| = \left\{\begin{array}{rcc} x - 4 & \text{if} & x \geq 4 \\ - x + 4& \text{if} & x < 4 \end{array} \right.\]

Answer 11

no! i win

Answer 12

tell him zarkon
tell him i win

Answer 13

you always win

Answer 14

:)

Answer 15

good answer

Answer 16

grrr

Answer 17

oh right! i did make a mistake. this is my template
\[f(x) = |x+4| = \left\{\begin{array}{rcc}
x + 4 & \text{if} & x \geq -4 \\
- x - 4& \text{if} & x < -4
\end{array}
\right.
\]

Answer 18

i copy and paste this in, but i didn't make all the necessary changes

Answer 19

sure...

Answer 20

ask zarkon it is the one i stole from him

Answer 21

whatever makes you feel better about the mistake

Answer 22

(pout)

Answer 23

i'm sure you will bust me soon lol

Answer 24

\[f(x) = |x-4| = \left\{\begin{array}{rcc}
x - 4 & \text{if} & x > 4 \\
0 & \text{if} & x=4\\
- x + 4& \text{if} & x < 4
\end{array}
\right.\]

Answer 25

fancy

Answer 26

yes...ty ;)

Answer 27

\[f'(x) =\left\{\begin{array}{rcc}
1 & \text{if} & x > 4 \\
\text{DNE} & \text{if} & x=4\\
-1& \text{if} & x < 4
\end{array}
\right.\]

Answer 28

so which piecewise is it? theoen with equal to or the one with DNE?

Answer 29

what?

Answer 30

this last thing zarkon wrote is the answer

Answer 31

the deivaitve of |x-4| does not exist at x=4
but exist everywhere else

Answer 32

or the first thing satellite73 wrote

Answer 33

for x>4 f'=1
for x<4 f'=-1

Answer 34

okay

Answer 35

where did the one come from?

Answer 36

\[\frac{d}{dx}(x-4)=1\]

\[\frac{d}{dx}(-x+4)=-1\]

Answer 37

oh okay understood