Question

use the definition of derivative to find f'(x)

Answer 1

\[f(x)=\sqrt{(x-4)}\]

Answer 2

Do you need help pluggin in or multiply by the the top's conjugate?

Answer 3

hmmm do you mean
\[ \frac{f(a+h)-f(a)}{(a+h)-a}\]

Answer 4

that is the definition of derivative @swissgirl
YES :D

Answer 5

so you're left with \[f'(x)=\frac{ \sqrt }{ h }\]

Answer 6

\[f'(x)=\frac{ \sqrt{(x+h)-4}-\sqrt{x-4}}{h}\]

Answer 7

\[f'(x)=\lim_{h \rightarrow 0}\frac{ \sqrt }{ ? }\]

Answer 8

WTFFFFFF

Answer 9

LOL

Answer 10

That latex fail

Answer 11

why is not going through?

Answer 12

oh gratz on 90 ss nin

Answer 13

Just btw my definition is not complete. This is the correct definition
\[ \lim_{h \to 0}\frac{f(a+h)-f(a)}{(a+h)-a}\]

Answer 14

\[f'(x)=\lim_{h \rightarrow 0} \frac{ \sqrt{(x+h)-4} -(\sqrt{x-4})} { h }\]

Answer 15

finally!!!!!!!!

Answer 16

f(x) = (x-4)^1/2
\[f'(x)= (\frac{ x-4 }{ 2 })^{\frac{ -1 }{ 2 }}\]

Answer 17

I didn't want to pick on you, @swissgirl LAUGHING OUT LOUD but yes. without the limit would be the MVT or the mean value theorem

Answer 18

o.o

Answer 19

no @shamil98 you've changed the entire thing by changing h = 2

Answer 20

h -> 0

Answer 21

you must be using a Plutonian Rule

Answer 22

Ok so basically the next step would be to multiply by the conjugate. Gonna write it out and scan it in cuz it will take me forever to type it in latex

Answer 23

I tried, omg that thing takes forever using the equation tool bar

Answer 24

you know at a glance, I thought it is not differentiable because it involves imaginary number and when that is the case, there's no limit with real number, hence no derivatives.

Answer 25

no there is a derivative just rewriting it.

Answer 26

i know that >.<

Answer 27

was showing @shamil98

Answer 28

how'd you scan that so quickly?

Answer 29

ummm it takes no longer than a half a second to scan

Answer 30

omg my scanner takes like a light year to scan a page

Answer 31

I have an issue I cant draw straight lines -_-

Answer 32

ruler usually solves that problem

Answer 33

lol thats what I usually hafta us

Answer 34

it is less of a technology than a scanner

Answer 35

hahahaha

Answer 36

@shamil98 yo
review this LAUGHING OUT LOUD so you can skip 2 years of college in math

Answer 37

Ya I am great at bargaining and I managed to still get warranty coverage after the warranty was over for a year and I complained that the scanning was slow so they sent me a newer model printer which works awesome

Answer 38

can you send me an extra scanner then?
I want the fujitsu desktop scanner. the brother machine I have is uber slow

Answer 39

ohhh I kept it and gave it to my bros ato destroy

Answer 40

bought it for 99 bucks just to have something to scan all my lab and experiment draft crap

Answer 41

ummm I have hp

Answer 42

mine was $150 I think

Answer 43

yo I saw the HP one, it's "touch" technology, but it's bulky and it gets smudgie

Answer 44

But I gotta scan in all my work every week so it was a necessity

Answer 45

ya the touch aint bothersome
But have not noticed it smudgy but then again I rarely print I usually scan

Answer 46

so do you think you can get the fujitsu desktop scanner? although it's not for high-paper scanning, it's fast and very small

Answer 47

for you or for me???

Answer 48

Not gonna waste my bargaining skills on you :P

Answer 49

http://www.fujitsu.com/us/services/computing/peripherals/scanners/scansnap/scansnap-iX500-deluxe-bundle.html

Answer 50

you're mean ... just mean mean mean cheese

Answer 51

OMG its expensive -_-

Answer 52

Totally not on my budget

Answer 53

it's actually cheaper now. it used to be around 900

Answer 54

ya still dont excite me

Answer 55

I've been waiting for that crap to be like 200 bucks so I can buy it, but they kept discontinuing the older models

Answer 56

Smart guys

Answer 57

blame the canadians ....

Answer 58

Did ya hear ma mayor is a crack head :D

Answer 59

it's fujitfrichinsu, it should be Japan

Answer 60

your mayor? or the re-elected Christie of NJ?

Answer 61

wait he's a governor LAUGHING OUT LOUD

Answer 62

Hey I dont live in NJ remembah

Answer 63

I would have bashed him for being unhealthy fat slob and use that against him
he neglects his own health and that is why he doesn't care about other people's health, which is the reason why he keeps cutting the university hospital's budgets

Answer 64

lol ohhh I forgot u live in NJ

Answer 65

I am a New Yorker... LAUGHING OUT LOUD

Answer 66

But u do live in NJ or at least at one point u did

Answer 67

idk I only have one place of residence

Answer 68

don't you live in like NJ, NY and Canada?

Answer 69

I visit those places but I only live in canada. I may be coming into NJ in 2 weeks -_-

Answer 70

laughing out loud

Answer 71

Its not funny!!! idk i may just stay at home alone. Seriously dont wanna head out there