derivatives

[meager trench]

hi team can smb guide me in the right direction for what i needa do for question 6 im so lost and might be fried for my test tmrw

[harsh gale]

!status

[covert cloak]

What step are you on?
1. I don't know where to begin.
2. I have begun but got stuck midway.
3. I got an answer but I was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above

[neat marsh]

@meager trench have u gone over derivatives yet or is this strictly an evaluate-the-limit problem?

[harsh torrent]

Convert csc to sec

[meager trench]

ive gone through derivatives yes

[meager trench]

1

[neat marsh]

does that limit look familiar to u

[meager trench]

yea like limit definition

[neat marsh]

factor a 3 out of the limit it might become clearer

[meager trench]

okay

then convert to sec ?

[harsh torrent]

Yes

[neat marsh]

csc(pi/2) is 1

thats the definition of derivative of csc evaluated at pi/2

[meager trench]

are you just isolating to find the derivative of csc

[neat marsh]

its essentially just $$ 3csc'(x) |_{x=\frac{\pi}{2}} $$

[devout anchor]

chikn

[neat marsh]

do u know how to take the derivative of csc?

[meager trench]

i know thatd be -csccot

i think

[neat marsh]

are u allowed to use that in the problen

problem*

[meager trench]

yea

teacher told us to memorize

[neat marsh]

there u go

[meager trench]

alright

let me review everything

[neat marsh]

recognizing derivatives from their limit definitions is useful for these types of problems

[meager trench]

mmhm

[neat marsh]

im curious how this would help

[harsh torrent]

Converting to sec(h) changes the problem from finding a derivative at x = pi/2 to finding one at x=0.

That limit will be in the form of this formula,

My logic is:
Identify the function as f(x) = 3sec(x).
Find the derivative f'(x) and plug in x = 0.

[neat marsh]

that is more reasonable tbh

derivative of sec is more memorable and widely known anyways

its also pretty straightforward to evaluate the limit after converting to sec by using conjugate

so thats some good insight too

[sly wren]

pull out constants.
diff theorem
3*lim f(pi/2+h)- f(pi/2)/h

[golden fjord]

there is a way to do this without any derivatives