#precalculus

1 messages Ā· Page 96 of 1

last palm
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I hope this helpsss

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Answer to thisšŸ‘†

keen delta
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honestly doing this rigorously would be hell I can only suggest using obvious quadratic equations that follow a and b since a would essentially always be true(in this case) and u have to find a function such that b is true

keen delta
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make the y positive
whatever is the direction of the x(+ or -) indicates if it goes upwards or downwards

keen delta
fresh jay
keen delta
# fresh jay Correct

šŸ˜”
A can't be true because if c is always real, it is already proven false by b

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since either f(x) or g(x) would have non-real roots which means f(c) can have c as non-real

fresh jay
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šŸ‘

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C is actually the main reason why I made that

keen delta
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I have no idea what a leading term is

fresh jay
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And asked Gemini to translate

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sooo

keen delta
#

shhh it's a common math term I'm just trying to ragebait people

fresh jay
#

šŸ¤”

silver robin
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Why are normal and tangents important in Conics?

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Need an intuitive answer

raw hill
# silver robin Why are normal and tangents important in Conics?

In a rough sense, normals and tangents describe how a curve interacts with a line at a point. When a light beam strikes a conic (parabola/ellipse/hyperbola), the beam reflects according to the law of reflection (which is measured with respect to the normal). For instance, a parabolic mirror can send incoming parallel light beams to a single focus. An elliptical mirror can reflect light from one focus to the other. So tangents help describe the local direction of the curve whereas normals give the direction used to predict how light beams bounce.

silver robin
raw hill
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ex. if you have curves representing lines of constant temperature in a room, then heat always flows along the orthogonal trajectories (hot to cold)

eager meteor
#

Doubt chat:

We know that e is a constant. So e raised to any power, say, x, will also be a constant. If I am correct, then why is the derivative of e^x with respect to x is e^x again? Shouldn’t it be 0, given the derivative of a constant is always 0? If there is, please show me the wrong in my thinking. Thanks šŸ™

uncut mulch
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x is a variable

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the value of e^x depends on the value of x

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taking the derivative of e^x wrt x,
you're considering how e^x changes as x changes

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that won't be 0

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d/dx e^x = e^x
is one of the definitions of e

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,w graph e^x

obsidian monolithBOT
uncut mulch
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,w graph e

obsidian monolithBOT
sonic hill
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(assuming c is not a function of x)

hushed sphinx
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The same reasoning would lead to the derivative of 2x being 0, since "2 is a constant, so 2 multiplied by any factor, say x, will also be a constant" .

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(On the other hand, since this is #precalculus, derivatives don't exist yet at all).

eager meteor
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Thx

eager meteor
hushed sphinx
eager meteor
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Thanks a lot

round geyser
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In angles of depre. and elevation, why is it (sqrt(6)-sqrt(2))

haughty crown
round geyser
karmic crow
gentle lantern
snow elm
snow elm
# karmic crow

ull get circle equation just substitute x values and get y

round geyser
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Is that a min or max word problem

rough leaf
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Wirhout using derivative

undone pumice
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3x+4y=25, 4x+3y=25. x-y=0, x=y. 3x+4x=25, 7x=25, x=25/7

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then calculate the mutual inclination using the slopes

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to get... arctan(7/24). i think

round geyser
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What are some exponents rules that is outside of this

eager meteor
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Then you have loga(0) = 1 for any a ig

uncut mulch
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log(0) is undefined

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you swapped the 0 and the 1

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also not any a,
a>0 and not 1

dreamy flicker
charred breach
dreamy flicker
charred breach
dreamy flicker
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Alr.

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Well then, input of log in all these should never be 0 or -ve

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And I think that's all there is to log

karmic crow
round geyser
uncut mulch
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multiply what

round geyser
uncut mulch
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wdym

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Can you write out the whole thing

round geyser
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Like this

uncut mulch
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is this an equation you're trying to solve or something else

round geyser
uncut mulch
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where'd that come from

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that made no sense whatsoever

echo sinew
obsidian monolithBOT
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Alberto Z.

echo sinew
obsidian monolithBOT
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Alberto Z.

neon comet
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guys can someone help me

toxic bluff
# neon comet

If you draw a picture it might give you some ideas.

neon comet
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no i tried ts shit 10 million times confused asf

echo sinew
white imp
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Guys

fossil kindle
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looks like pythagorean to me

round geyser
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I’m also doing that too

round geyser
echo sinew
grand inlet
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does anyone know how to find range and domain??? i've been struggling on it recently and i want to know how since i believe it's fairly simple

cunning dust
plush carbon
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Does anyone know any good videos or websites that can teach inverse trig functions?

obsidian slate
# plush carbon Does anyone know any good videos or websites that can teach inverse trig functio...

šŸ“š Notes on TG:- https://t.me/jeeenglishbyunacademy

āž”ļø Problem Practice sheet for ITF:- https://drive.google.com/file/d/1_Mcq86bUENMCBjBG6xgLVRy2oIk3OLKO/view?usp=sharing
Unlock the complexities of "Inverse Trigonometric Functions" with our detailed Class 12 session, perfect for JEE Main & Advanced preparation. Master key con...

ā–¶ Play video
hushed sphinx
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<@&268886789983436800> mrbeast

plush carbon
haughty crown
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Why was he here

hushed sphinx
# haughty crown Mr who

There's a persistent group of scammers who use subverted Discord accounts to post false claims that the youtuber (I think?) MrBeast has opened an online casino and is giving away large amounts of money as sign-up bonuses. All lies, of course, just the bait for an advance-fee scam.

haughty crown
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Post screenshots of his Twitter or something?

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I’m never sure if it’s a bunch of scammers or a virus that infects accounts

hushed sphinx
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Well, screenshots that purport to be that.

haughty crown
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Right right right

hushed sphinx
#

Definitely scammers. Most likely they buy the subverted accounts from someone else who farms them with cruder bait (in the vein of steam giveaways etc) -- at least one should hope there's less than one person falling for the casino scam each time they post it, so they'll need an additional source. But this is not really known.

haughty crown
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Cruder bait lmao

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Man I hope I don’t fall for stuff like that when I’m geriatric

round geyser
raw hill
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me when roots of unity again catscream

bold carbon
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i dont think -1/2 is a root

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there should be 9 complex roots and 1 real root

brisk raft
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its a lot easier like that

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you would get $\left(\frac{x}{x - 1}\right)^{10} = 1$

round geyser
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Ye

obsidian monolithBOT
round geyser
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I mean it’s no solutions

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It’s 1 real and 8 complex roots

brisk raft
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so you made a mistake

round geyser
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One no solution

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1≠0

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Okay

brisk raft
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i am still quite confident you solved it wrong

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$$\frac{x}{x - 1} = {\exp(i 2\pi k / 10)}_{k = 0}^{9}$$

obsidian monolithBOT
brisk raft
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this should yield 1 real and 9 imaginary

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wait

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i see my bad

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because exp(0) = 1 but x/(1-1) isnt defined

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sorry šŸ˜…

round geyser
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Okay

exotic barn
tough flare
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$ln (y)$ just means what power of e equals y?

obsidian monolithBOT
#

Ujjawal Gupta

tough flare
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Like $e^{?} = y$

obsidian monolithBOT
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Ujjawal Gupta

tough flare
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?

exotic barn
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yes

tropic fossil
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yo whats the chain rule?

undone pumice
undone pumice
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ye

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isok

haughty crown
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Chain rule.

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Chain rule is pain.

orchid urchin
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wym by that

haughty crown
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What’s confusing

orchid urchin
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how is it painful its super easy no?

haughty crown
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If I’m js casually differentiating my ass ALWAYS forgets chain rule

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It is super easy

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I js forget it

orchid urchin
haughty crown
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No

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Because now I’m thinking about it

orchid urchin
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but if u forgot

haughty crown
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But normally like a 25/75 wrong/right

orchid urchin
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in what way do u forget it

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do u just differentiate ln(3x^2 + 9) into 1/(3x^2 + 9)

orchid urchin
haughty crown
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Yes bro

orchid urchin
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hmm

haughty crown
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It just slips my mind

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I’m better now

orchid urchin
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thats good

orchid urchin
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because it does work on everything

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ln(x) using chain is still 1/x

haughty crown
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Too much thinky thinky

orchid urchin
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or sin(x) is still cos(x)

orchid urchin
haughty crown
round geyser
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Hey, I heard there is a inverse pythagorean theorem

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Which is 1/a^2 + 1/b^2 = 1/c^2

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Does that work

orchid urchin
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for the sake of it being automatic?

haughty crown
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Nah

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Enough normal practice will get me there

orchid urchin
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fair enough

haughty crown
round geyser
orchid urchin
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its just the reciprocal

round geyser
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Okay is that useful

round geyser
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And where would u use it

orchid urchin
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cuz division by zero is a no no

haughty crown
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What abt a 345 triangle

round geyser
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Ik there is sin^-1, cos^-1, and tan^-1

haughty crown
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But wait wait

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For a triangle with legs of 3 and 4, hypotenuse has to be 5

round geyser
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Ohhh

orchid urchin
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for normal numbers its fine tho

round geyser
orchid urchin
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actually wait i lied

round geyser
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a and b are legs and h is the altitude

haughty crown
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Are we SURE here

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The numbers do not seem like there working out

round geyser
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Look

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It looks like this

orchid urchin
# haughty crown Are we SURE here

yes because 1/h^2 = 1/a^2 + 1/b^2, youd just find a common denominator for 1/9 and 1/16 which is 144 and get 25/144, and then use comparison.

round geyser
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3-4-5 triangle and want to find the height

haughty crown
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Oh I see now

haughty crown
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It would be the least distance between the right angle and the hypotenuse

round geyser
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h=12/5

haughty crown
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I was misreading that

orchid urchin
haughty crown
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This feels like the wrong channel for ts tho

orchid urchin
round geyser
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Yea

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Is it a good formula to remember

orchid urchin
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3 * 4 = 5h -> 12 = 5h -> h = 2.4

round geyser
orchid urchin
# round geyser You can do that?

its from the area = 1/2 base times height, and you know for specifically a 3-4-5 triangle that 1/2 * a * b = 1/2 * c * h, giving a * b = c * h

round geyser
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Ohhh

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Can I use that for bearing problems

orchid urchin
orchid urchin
# round geyser Can I use that for bearing problems

if the two legs a and b are already perpendicular to each other then you can treat leg b as the base and leg a as the height, which gives 1/2 * a * b. then now imagine rotating the triangle so it sits on its longest side, the hyp c, in this orientation the altitude h is the height giving 1/2 * c * h, and then you set them equal which implies a * b = c * h or h = (a * b)/c

round geyser
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Since I’m doing bearing type 2

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The direction is now N/S (degrees) E/W

orchid urchin
round geyser
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That

long bane
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chat idk how to do law of sines- ambiguous cases can someone help
like how do i find how many solutions from just B=36degrees, a=5, b=8 😭

round geyser
undone pumice
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then do 180 - first possible angle

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and if that plus the other possible angle is less than 180 2 solutions

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i think its kinda been a while since i did it

haughty crown
fringe quarry
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Hello I'm new here.

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I think I chose wrong subject, I'm gonna change it.

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Ok bye!

tough flare
shut tangle
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What's precalculus

gentle lantern
flat crystal
# shut tangle What's precalculus

(I haven't studied in the US so this might not be 100% accurate)
Calculus is a very big subject that use alot of concept that you didnt even heard about before
And pre-calculus will prepare you for that

You will see alot of new mathematic objects such as log, limits, trigonometry identities
You will also go over alot of new functions (trigonometry functions, log, expo, rational)
You should also see vectors (which are very useful in physics by the way)
I've heard that you also see matrix but I'm not sure
And more things about trigonometry because it's so useful

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(Sorry for the big message)

haughty crown
round geyser
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That’s what I did

viscid thistle
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Somebody give me I question, I wanna solve one real bad

tame shard
obsidian monolithBOT
#

multiplexer

tame shard
viscid thistle
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Thanks, give me 5 mins

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Or 10..

tame shard
viscid thistle
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How are you supposed to solve that?

tame shard
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It took andrew wiles (someone with a PhD in math) 7 years to prove this

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:3

viscid thistle
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What the... You really gave me a question that took 7 years to prove xd

tame shard
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And that is with a PhD

viscid thistle
tame shard
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And works from multiple other mathematicians

tame shard
viscid thistle
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XD

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Ok pal

urban kernel
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(Bullying pre-unis)

round geyser
#

What

lucid trench
#

helloo?

undone pumice
lucid trench
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hi i dont really have a math problem but id like to ask for some advice regarding math.. lol is that ok?

undone pumice
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sure

lucid trench
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ok so its also abt gpa

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ok so

undone pumice
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kk

lucid trench
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i have a question what are the best AP's to take that would like significantly boost my gpa

undone pumice
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....err

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All AP classes are weighted the same (5s on a 4 point GPA scale)

lucid trench
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ooh

undone pumice
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for example: i have 2 AP classes, 2 honors, 2 regular

lucid trench
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mmm

undone pumice
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so 5+5+4+4+4+4=10+16=26. 26/6=4.3... ish

lucid trench
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ooh thats thats good

undone pumice
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Well my school weights honors as 5s

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but I believe universities do not

lucid trench
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ooh

undone pumice
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(So I have like a 4.6... ish >.< still not val cus of PE and Chinese, which do not count as honors)

lucid trench
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wow nice

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can i ask what AP's u take?

undone pumice
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Precalc

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And Comp Sci Principles

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(I'm a freshman, so I can't take others.)

lucid trench
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oh man are they hard?

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FRESHMAN OH no im cooked

undone pumice
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not really

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Next year I'll be taking AP World and Calc AB

lucid trench
#

oohh

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see

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i was thinking

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im not sure if you know what this is

cyan quiver
#

can someone help me with this

lucid trench
#

can i dm you if thats fine lol?

undone pumice
#

sure

fossil kindle
#

What

haughty crown
#

Chat you ain’t seen nothing until you take AP macro/microeconomics with a teacher that knows less than you do

haughty crown
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Awful

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Exam is Monday

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Haven’t finished content

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Coulda finished it like last month if we locked in

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Instead we did push ups

undone pumice
#

šŸ„€

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im suddenly grateful we finished course content in both my ap classes

haughty crown
#

Always be grateful

undone pumice
#

macro/micro are senior classes at my school so thats a future me problem

haughty crown
#

Bc got done earlier this week but I’m behind

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So I still gotta learn the hard stuff

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My physics class has been done but she lowkey js neglected to teach some stuff…

undone pumice
#

oop

haughty crown
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Nah it’s fine tho I’m gonna get a 6

undone pumice
#

lol

tough flare
#

Lets say that we have time and position axes, and we plot the movement of a fly, so it's random data, now let $f : t \to p$, so is $f$ a perfectly defined function?

obsidian monolithBOT
#

Ujjawal Gupta

raw hill
# tough flare Lets say that we have time and position axes, and we plot the movement of a fly,...

I assume you meant to ask this:
\begin{tcolorbox}
Suppose we plot the movement of a fly on a coordinate system with time $(t)$ and position $(p)$ axes. If we define a mapping $f$ from time to position ($f:t \to p$), is $f$ a well-defined function?
\end{tcolorbox}
\vspace{0.3cm}

In this case, the answer is yes. Recall a function is well-defined if every input from its domain maps to \textit{exactly} one unique output. A physical object can cannot be in multiple places simultaneously but still must exist, so the fly occupies exactly one specific $p$ at any given time $t$.

obsidian monolithBOT
#

Civil Service Pigeon

tough flare
tough flare
raw hill
# tough flare Ok then, whats equal to f(t)?

$f(t)$ is simply the physical position of the fly at time $t$, as you said. A function doesn't have to possess some neat, explicit algebraic equation like $f(t)=t^2+3$ to be valid. As I said earlier, a function is strictly defined as any rule or mapping that assigns exactly one output to every input. So the rule doesn't have to be an equation, but can also be an empirical data set, a lookup table, or just physical reality. For example, if the fly was at the point coordinates $(2,4,1)$ at time $t=5$, then you'd simply have $f(5)=(2,4,1)$. \

Tldr: The reality of the fly's location \textit{is} the function.

obsidian monolithBOT
#

Civil Service Pigeon

raw hill
tough flare
obsidian monolithBOT
#

Ujjawal Gupta

raw hill
#

(2,4,1) are coordinates in 3d space

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Not the coefficients of a normal vector or smt

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Idk where the =5 comes from in any conceptual sense

tough flare
#

How can I represent this data as a linear equation?

raw hill
#

I think you’re doing too much to escape from the abstraction to the point where it’s wrong

tough flare
#

Which then can be solved and one can also find best solution possible through projection

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Like 3 points (4,2,8), (2,4,1), (3,7,1) can be represented as $\begin{bmatrix}4 & 2 & 3 \ 2 & 4 & 7 \ 8 & 1 & 1\end{bmatrix}$?

obsidian monolithBOT
#

Ujjawal Gupta

raw hill
# tough flare Like 3 points (4,2,8), (2,4,1), (3,7,1) can be represented as $\begin{bmatrix}4 ...

You can write 3D coordinate vectors as columns of a matrix, but this is more of an organisation tool than anything unless you're atually going to do something with the matrix. In fact, putting the coordinates in the matrix has completely dropped $t$ (the domain of your function $f$). So if you wanted to use projections to find a line or plane of best fit (that's my best possible guess for what you want, it's very unclear), you'd no longer have the corresponding times to model the movement. And again, the matrix is just an organisational tool -- it doesn't magically force a fly's highly erratic (typically non-linear flight path) into a "nice" linear system.

obsidian monolithBOT
#

Civil Service Pigeon

tough flare
tough flare
obsidian monolithBOT
#

Ujjawal Gupta

raw hill
#

Like I said, flies are famous for moving in highly erratic and non-linear paths

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forcing a line/plane of best fit through that chaotic data is probably going to give you a largely meaningless trajectory

tough flare
raw hill
#

....

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idk how that's happening

fresh prawn
#

Hello guys! Can someone help me with the "properties" of integrals?

raw hill
#

wrong channel

fresh prawn
#

Ohhh tanks! sorry

raw hill
green crown
#

I need a bit help with the task below. I am just wondering - would there be infinitely many solutions for this problem?

The task:
Two planes are parallel to the xy-plane and have a distance of 6 from this plane. Find an equation and a parametric representation for each of these planes.

tame shard
green crown
#

This would be the xz-plane: y = 0

tame shard
#

iw as tripping

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i was thinking of 2 parallel lines to x = 0

green crown
#

Ohh

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But maybe i need to first find the parametric equation for the xz-plane?

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In order to find the two other planes

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But if these two planes are parallel to the xz-plane, would they have the same normal vector as the normal vector to the xz-plane?

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<@&286206848099549185>

heavy pewter
#

they don't have a fixed let's just say y intercept

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like you can fix two parallel planes of distance 6, and move them about the y axis

green crown
pale void
heavy pewter
#

because they still satisfy the condition, that means that there are infinite solutions

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to your condition

green crown
green crown
green crown
#

Oh okei

heavy pewter
#

well what do you mean exactly

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there's a really easy method with vectors and it is quite illustrative

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but i'm not sure if that is applicable for your case

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but if you want to like definitely prove it then sure use equations

green crown
#

Okei wait, so in order to find a parametric equation for the two planes i need to find a point it passes and two vectors (non-parallel vectors) that are parallel to the plane

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I believe

gilded scaffold
#

Is Pre-Calculus just Functions and Trigonometry? Is Algebra is also involved here?

green crown
#

I think it includes algebra too

undone pumice
#

in my class, we have these 4 units

gilded scaffold
exotic barn
#

any other construction would either fail to be parallel to the xy axis or not have distance 6 anyway

green crown
green crown
green crown
#

And the xz-plane would have this equation: y = 0

exotic barn
#

Though even with one line, there would be only one plane associated with it anyway

green crown
exotic barn
green crown
#

I will try to solvee it noww

exotic barn
#

And yeah as the task says, 2 planes at most is only possible

green crown
#

Understood

#

Let mee try

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Soo the equations for the two planes that are parallel to the xz-plane (the plane in the middle) would be y = 6 and y = -6

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And noww i just need to find the parametric equation

exotic barn
#

yes

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You can easily pick 3 points A,B and C and set up E : x = A+sAB+tAC

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Since any point with y=6 for example, is just (x,6,z)

green crown
#

So plane y = 6 passes this point (0, 6, 0) while plane y = -6 passes this point (0, -6, 0)

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Right?

exotic barn
#

yes

green crown
#

And noww i need to find the direction vector. Since they are all parallel, they would all have the same direction vector, which would be (1, 0, 1), or as long as it is on the form (a, 0, b).

exotic barn
#

What do you mean by

Since they are all parallel

green crown
#

$l: \begin{cases} x=s\y=6\z=t\end{cases}$

obsidian monolithBOT
green crown
#

I think this would be correct for the plane y=6

exotic barn
#

you just picked (1,0,0) and (0,0,1) which are trivially perp to (0,1,0)

green crown
exotic barn
#

Oh you meant that

green crown
#

Bahaha yess

exotic barn
green crown
#

$E: \begin{cases} x=s\y=6\z=t\end{cases}$

exotic barn
#

but nothing to be concerened of mathematically

obsidian monolithBOT
green crown
#

Like this?

exotic barn
#

you can't copy directly as it omits the double backslah

#

yea

green crown
#

$\alpha$

obsidian monolithBOT
exotic barn
#

you can use any letter

green crown
#

Oh okai

#

Got it

exotic barn
#

any letter to your liking

green crown
#

$\alpha: \begin{cases} x=s\y=6\z=t\end{cases}$

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Ohh

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Wait

exotic barn
#

fell twice for it

obsidian monolithBOT
green crown
#

And the second one would be

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$\beta: \begin{cases} x=s\y=-6\z=t\end{cases}$

obsidian monolithBOT
green crown
#

For instance

exotic barn
#

yea

green crown
#

Thank youuu

exotic barn
#

No problem

rustic cobalt
#

Guys is it encouraged to use log differentiation when approaching questions with e^x? I just started and I always use the basic chain rule and quotient rules

exotic barn
#

<@&268886789983436800> sus behavior

gilded steppe
rustic cobalt
#

Do I jsut just add a ln ?

rustic cobalt
tame shard
rustic cobalt
#

Makes sense

rustic cobalt
#

And use log rules?

green crown
# rustic cobalt Do I jsut just add a ln ?

What do you mean? It depends on the assignment - for instance if you want to solve for x in this equation e^x = 2 then you can apply ln (the natural logarithm) to both sides in order to solve for x, which would give x = ln(2).

rustic cobalt
#

Nah let’s say we have have f(x) = cos(x) plus 5x / 2x^2 * e^2x and we got to find f prime of 1. Instead of using chain rule and quotient rule can we add logs to make it simpler?

dim oyster
#

guys any book recommendations for precalc self study

rustic cobalt
#

Liek are u allowed to add ln to both sides in a function?

rustic cobalt
#

I mean just take the basics of college algebra

#

I don’t have pre calc in our country, but our units are functions, then calculus

green crown
#

I am not suree

#

I dont think i have ever done that

rustic cobalt
#

K

rustic cobalt
green crown
round geyser
mossy quiver
round geyser
#

Then got x^2-xy+y^2=3

mossy quiver
#

you mean y^2?

round geyser
#

Yes

mossy quiver
#

okay, next?

round geyser
#

For plugging x^2-xy+y^2

mossy quiver
#

i don't see why not

round geyser
#

When I did that it’s 9=x^2+2xy+y^2

#

x^2-xy+y^2=3
x^2+2xy+y^2=9

mossy quiver
#

that works, but a bit overcomplicated

round geyser
#

I’ll do elimination

mossy quiver
#

just note that x^2 - xy + y^2 = x^2 + 2xy + y^2 - 3xy = (x + y)^2 - 3xy = 3

#

you can easily calculate xy

#

since you have the exact values of x + y and xy, the next steps are easy

exotic barn
green crown
exotic barn
#

simplify differentiation yes

green crown
#

Staaar

green crown
#

Got it

#

Nooo

#

Not that emoji bahahaha

round geyser
candid kite
#

guys help 😭

#

for c, i know what to do, but theres too much i need to differentiate so idk what order to do

pale void
#

please do not ping helpers here

candid kite
pale void
#

ill give you a hint

candid kite
#

i know i need to use chain rule but ive just started trig, so im kinda confused on where to start with chain rule

pale void
#

$\frac{d\cos^4(5x)}{dx} = \frac{d\cos^4(5x)}{d\cos(5x)}\times \frac{d\cos(5x)}{d(5x)}\times \frac{d(5x)}{dx}$

obsidian monolithBOT
#

Annie Maqionde

pale void
#
  1. power of the function
  2. look at the argument, you have the form for derviative of cos y, right?
  3. argument w.r.t. x
candid kite
#

i dont understant how its become a fraction now

#

i dont get it 😭

floral barn
candid kite
#

yes

floral barn
candid kite
#

but dont i have to derive the cos too?

mint sequoia
#

No need.

#

It is in term of f o g.

floral barn
candid kite
#

so would it come to 60 cos^3(5x)?

round geyser
floral barn
#

You have to keep doing it until the derivative becomes 1

candid kite
mint sequoia
#

Basically derivative of cos(5x) and multiply with derivative of cos^4(5x).

candid kite
round geyser
#

Ok

candid kite
#

i feel like i did these wrong

mint sequoia
#

That explanation written by Annie was correct, but quite long.

#

And do not forget the constant 3.

candid kite
#

12 (cos^3(5x)*-sin^3(5x))?

#

bro im so cooked

undone pumice
candid kite
undone pumice
#

double chain rule? i think

candid kite
#

but not double

undone pumice
#

like when u do chain the first time

#

you take the inner function as cos5x

candid kite
#

yeah

mint sequoia
#

D/dx is just apply derivatives.

undone pumice
#

and u have to differentiate the inner function for the chain rule right? well the inner function's derivative is found with the chain rule

mint sequoia
undone pumice
candid kite
undone pumice
#

remember the inner function is 5x

mint sequoia
#

You missed 5x inside.

#

Chain rule again.

candid kite
#

what is the final answer so i can try figure out how to get there

ancient inlet
undone pumice
#

think about how to apply chain rule to d/dx(cos(5x))... the inside... the outside...

ancient inlet
#

If use try integrating sin5x you wouldn't get cos5x right?

undone pumice
#

oh this is the precalc channel..

ancient inlet
#

LOL

undone pumice
#

fah i just remembered i have ap classroom work

#

for precal

#

šŸ„€ im sure i can speedrun like half of a practice exam

undone pumice
ancient inlet
undone pumice
#

šŸ„€

undone pumice
ancient inlet
undone pumice
#

xd

ancient inlet
#

I do love mental math

undone pumice
ancient inlet
#

What's FRQ?

undone pumice
#

frq = free response question

candid kite
undone pumice
#

u multiply by teh derivative of the inside function

#

the isnide function is 5x

#

d/dx(5x)=5

#

5*-sin(5x)

#

d/dx(cos5x)=-5sin(5x)

candid kite
#

but yes i need to add the sin(5x)

undone pumice
#

rest of it looks good

candid kite
undone pumice
undone pumice
candid kite
undone pumice
#

time to grind this take home practicce exam calc mcq igs

candid kite
#

if theres a coefficient inside the sin() does that count as another different function?

undone pumice
#

outer function as sin(x) and inner function as (whatever it is inside sin)

candid kite
#

cuz the next question is y=(sin 3x)(1 - 2 cos x)

undone pumice
#

ah

undone pumice
candid kite
undone pumice
#

uhh

#

i think so

ancient inlet
candid kite
#

thanks

undone pumice
#

similar to the 5x one, you take derivative of 3x as 3 and multiply

candid kite
#

yeha

undone pumice
undone pumice
#

like after i graph is there a way to find inflection points cus i can't find a way in desmos and my calculator is lowkgenuinely dead

undone pumice
#

im not too keen of that idea either cus with the 2pi/365(t+15) i think thatd be chain rule

candid kite
#

but i dont really know any other way to find concavity other than double der

undone pumice
#

idk either

#

šŸ’€

#

maybe i just plug in at 299 and 301 and see if its increasing or decreasing, then guess with a 50/50

candid kite
#

lemme try it on calc

#

wait maybe you can do the sign test

undone pumice
#

well its a decreasing function at 300 so theres that

undone pumice
#

oops

cerulean cape
#

if u dont wanna do double deriv

undone pumice
#

ya but how do i find concavity from there

#

i have it graphed in desmos cus thats how i was looking at it at 300 but

ancient inlet
candid kite
cerulean cape
#

just at 300 is it decreasing or increasing

candid kite
#

😭

undone pumice
cerulean cape
candid kite
#

sorry

cerulean cape
#

lowk dont remember if they taught us this in 9th

undone pumice
#

i just feel like my precalc teacher will chew me out if she sees me doing that (cus we have to submit our work :c)

undone pumice
cerulean cape
#

yea I dont remember if we did this I think we were alr doing linear alg

#

jk

scarlet cedar
undone pumice
#

ykw what looks concave up imma call it a day and move on šŸ„€

candid kite
#

bro im in 12th and we just started ts 😭

undone pumice
#

ye

undone pumice
#

im teaching myself calc

scarlet cedar
#

Derivative is year 10

undone pumice
#

but im in precal

undone pumice
#

here at my school

#

precal is standard 12th

#

11th advanced

ancient inlet
undone pumice
#

10th advanced honors

scarlet cedar
#

Interesting

undone pumice
#

but im in the US so my classmates are slow tbf

scarlet cedar
#

The word "US" explained it all

candid kite
#

im in australia so we started calculus/derivatives in year 11

#

im in year 12 now

undone pumice
#

and the advanced honors track is calc in 11th

candid kite
#

so we're going into expos and trig calculus

undone pumice
#

ah interesting

#

u didn't learn trig calc in 11th?

candid kite
#

no

#

just normal differentiation

#

and the first thing we did in year 12 was double derivatives

scarlet cedar
#

Trig calc supposed to be taught in lat yr 10

#

then they will revise it in uni

cerulean cape
#

I alr graduated so

#

I lowk forget

#

how it was

candid kite
#

im graduating in october

undone pumice
#

my school has like calc ab and bc

cerulean cape
#

I think we did calc 3 senior yr

undone pumice
#

oh wow

cerulean cape
#

or calc 2 idk

#

Im doing ee rn

candid kite
#

bro this math test is on friday and i cant even do simple shi 😭 im so cooked

undone pumice
#

šŸ„€ nunu u got this

#

just remember like the basic derivative rules and such

#

grind any practice problems u find šŸ„€

candid kite
#

yeah thats what im trynna do rn

#

ive got 4 days

undone pumice
#

šŸ™ i got math finals tuesday, wednesday, friday. and then ap exam on tuesday and then my math teacher said shes gonna make us learn calc until june

candid kite
#

i didnt go to school today (mostly because i overslept my alarm) so i can study for this

undone pumice
candid kite
#

am i getting somewhere

ancient inlet
undone pumice
#

the second part

#

the 1 shouldn't be there

#

i think

ancient inlet
#

Differentiate 1 - 2cosx

#

If you differentiate constant what would it be?

candid kite
ancient inlet
scarlet cedar
undone pumice
candid kite
#

how would i multiply cos3x with cosx

undone pumice
#

or well -6cos3xcosx

candid kite
#

thanks

undone pumice
#

but im confused on um

#

k(x)

#

is it supposed to be like

#

1-cos^2x/cos^2x instead of tan^2x and such or like

ancient inlet
#

It said cosine appears once only

undone pumice
#

oops nvm

undone pumice
#

1/(cos^2(x))

candid kite
#

im cooked

#

im gonna fail this test bro

ancient inlet
candid kite
candid kite
undone pumice
ancient inlet
#

2nd line

#

Is your final answer

candid kite
#

yeah i know, ignore the 3rd

candid kite
#

thank youuu

ancient inlet
#

Would this be correct?

undone pumice
#

Ummm my approach was

#

Csc^2-cot^2 is 1

#

Tan^2x is sec^2x -1

#

Sec^2x is 1/cos^2x

#

Idk if that’s right tho

#

lwkgenuinely im bouta just hop on brawl stars trig work is kinda ragebaiting me

undone pumice
candid kite
undone pumice
undone pumice
ancient inlet
#

Everyone lazy rn

undone pumice
#

And I still have math finals to study for but who cares

candid kite
#

the academic stress isnt worrying me, whats worrying me is how im straight up ignoring it

#

šŸ’€

undone pumice
#

šŸ˜”

ancient inlet
undone pumice
#

šŸ„€

candid kite
#

i can not lock in

undone pumice
#

nunu u can do it (says while continuing to grind brawl stars)

undone pumice
#

uh

#

y' should be the slope

#

then calculate how much um... y intercept? to add

#

i think..

candid kite
#

yeah but

#

if m is 2cosx

#

lik

undone pumice
#

pi/3

ancient inlet
candid kite
undone pumice
#

it says

#

calculate the equation of the tangent

#

at x=pi/3

#

so we want the specific slope at pi/3

#

so we need to plug in for that

candid kite
#

the equation of the tangent is y=mx+c

#

like plus pi/3 in the 2cosx?

undone pumice
#

2cos(pi/3) = m

candid kite
#

i did that befpre

#

but then how do we get the +c

undone pumice
#

if you think about it

candid kite
#

2cos(pi/3) = 1

undone pumice
#

2sin(pi/3) is

#

sqrt3

#

right?

#

and right now with a slope of 1

#

what would the tangent line evaluate to at pi/3?

#

before adding a intercept

#

don't overthink it

fossil kindle
undone pumice
candid kite
#

i used to like it

undone pumice
#

cus rn we have basically y=x

#

so the difference between the values of sin(x) and y=x

#

would be... (dont need to simplify)

tulip fern
#

another helper ping

candid kite
#

0?

undone pumice
#

well

#

if you have 2sin(pi/3) as sqrt3

#

and y=x at pi/3 as pi/3

#

whats the amount you need to add to make the tangent line go up to touch the curve?

candid kite
#

im so confused

#

sorry

undone pumice
#

as you can see we want the line to move up a certain distance to touch the graph

#

(btw, 1.73... number is sqrt3)

#

so that distancce

#

is sqrt3 - pi/3

#

as such

#

sorry idrk how to explain it

#

back to brawl

candid kite
#

i'll try and figure it out

undone pumice
round geyser
weary flower
#

Can anyone help me on this question? Im not good at matricies or vectors so its confusing.

wicked vapor
#

I found this bullcrap question

#

I'm not asking for an answer but like it's so weird

weary flower
#

What is this šŸ„€

devout bone
#

and the angle between a plane and a line is the angle between the normal of the plane and the line

weary flower
#

thanks for the help!

fossil kindle
hardy raft
hardy raft
wicked vapor
#

It's arithmetic but clunky

wicked vapor
glad sun
#

and here i am taking precalc 12 in canada where the worst thing i would see is trig

glad sun
wicked vapor
glad sun
#

yeah bc of lagrange interpolation, whatever the flippers that is

weary flower
bold crag
next moat
#

now who is pinging me in PRECALC/

jade scaffold
#

any1 explain me this i just strted calculus

#

or deravatives

earnest marsh
jade scaffold
earnest marsh
#

have not??

jade scaffold
#

mb

earnest marsh
#

then i think it is time to study logarithms ig

jade scaffold
#

i will

fossil kindle
keen delta
# jade scaffold any1 explain me this i just strted calculus

take the natural logarithm of y=a^x
that gives us lny=lna^x=xlna which gives us lny=xlna
now I'm pretty sure this is implicit differentiation(same thing basically) but you find y'(same thing as dy/dx) after multiplying, this is also basically chain rule as y is a function of x and y' is the derivative
so this gives us: y'/y=lna
which can then be done as y'=lna * y=lna * (a^x)

#

in case you're wondering what a logarithm is

#

ionknow

round geyser
undone pumice
#

the degrees are equal

round geyser
#

Yes

keen delta
#

I think

#

oh yeah that's it

round geyser
#

Ye

#

The domain is x≠-d/c

smoky mural
#

Hi everyone

#

Can l post a question

tender questBOT
# smoky mural Can l post a question

Asking the actual question right away is more likely to get responses.

Asking "Can I ask...?" or "Does anyone know about...?" doesn't give people enough information to decide whether they can help, and answering can feel like a promise to help with the actual question, which they might find themselves unable to.

orchid urchin
obsidian monolithBOT
#

text book

orchid urchin
#

e an ln are inverses and that is why that works

#

and then you use the chain rule

#

since its not in the standard e^x form

orchid urchin
#

they are quite simple though

jade scaffold
wicked vapor
#

Logarithms should be taught before differential calculus

jade scaffold
#

in next class (lecture)

hoary zephyr
# wicked vapor Tf

shouldn't differential calculus and integration be taught first , bc ln(x) is the integral of 1/x

uncut mulch
#

logs are the inverse of exponents

#

and first appear in that topic

jagged dust
undone pumice
#

2 to what power js 8

undone pumice
#

That’s the opposite of 2 to the power of 3 is 8

jagged dust
#

but expo was before log or was log before expo

undone pumice
#

So log is an operation that can undo exponents. like multiplying and dividing

undone pumice
jagged dust
#

and later differentiated

undone pumice
#

Exponents I believe logs were calculated

jagged dust
#

was logs discovered to counter issues of math in which alg cant enter?

undone pumice
undone pumice
#

I’m not sure when the calculus implementation of exponents and logs was tho

jagged dust
#

exponents should be before because they come naturally not saying log is artificial but exponents are moe out there in human and space logic than log

jagged dust
undone pumice
#

Idrk math history

jagged dust
#

hm

#

im going off intuit here

wicked vapor
#

Roots and logarithms

jagged dust
#

So log is the longer more accurate one?

wicked vapor
#

No

#

They do different things

#

You can't compare them, they're used for different scenarios

wet ingot
#

hi

round geyser
#

Can you do factor with x^pi =1

echo sinew
#

Idts

astral apex
# jagged dust exponents should be before because they come naturally not saying log is artific...

it appears that while basic facts about exponents were known since antiquity, the modern concept of an exponential function and its derivative didn’t come until after people noticed the area under a hyperbola is related to logarithm tables.

Napier/Briggs: logarithms as computational tools
Saint-Vincent/Sarasa: natural log as hyperbola area
Newton/Leibniz: calculus makes d/dx[ln x] = 1/x
Bernoulli/Euler: e, exponentials, inverse-function viewpoint, and d/dx[e^x] = e^x

#

the thing is it took a long time for people to formalize what a function is and what should count as a function

jagged dust
astral apex
#

I'm not sure what you mean

#

but something like $2^{\pi}$ took a while for people to come to grips with

obsidian monolithBOT
#

ManifoldCuriosity

astral apex
#

or $\sqrt{2}^\pi$

obsidian monolithBOT
#

ManifoldCuriosity

fair garden
#

yo guys, what on earth is Limit?

undone pumice
#

also one sided limit, from the left/right

fair garden
undone pumice
#

what are you looking for...?

fair garden
#

sorry, I asked the wrong question

#

where does limit comes from?

astral apex
#

it's calculus

#

though you get a quick intro to the idea at the end of precalc

fair garden
#

I'll go to calc chat

#

if there's such

astral apex
#

there is one, I think it's fine to ask here though

#

I'm not quite sure what you mean about where limit comes from

#

do you mean what motivates the concept of limit?

undone pumice
astral apex
#

in precalc?

undone pumice
#

ye

fair garden
#

nay, what I am asking is the formal definition of Limit

fair garden
undone pumice
#

<@&268886789983436800>

undone pumice
#

bcs

orchid urchin
#

so many ppl asking about calc 1

undone pumice
#

the video we watched said f(x) and our worksheet used g(x) and they told me "its not the same function" with a straight face

undone pumice
astral apex
undone pumice
#

they were a senior btw like a full grown adult with a mustache

orchid urchin
fair garden
undone pumice
#

it was a formula

astral apex
#

yeah, that's the case of a function limit, with the variable approaching a finite number, and the value being finite

undone pumice
#

which used f(x) as an example

#

and the worksheet had us calculate it with a function g(x)

orchid urchin
#

like f(x) = x^2 and g(x) = x^2