math-help

[night flint]

🙂

[graceful remnant]

law of cosines

[tardy crown]

how i can resolve this? |((3-4x)/(2x-3))| ≥ 2

i need the interval notation, and i now is (3/2,∞) but i don't get the process

[left knoll]

You've to apply the properties of absolute value

[left knoll]

And the solution interval is this:

[left knoll]

Yeah, i found like this, too

I'm sorry about my writing :/

[tardy crown]

@left knoll @left knoll thx work very well!

[left knoll]

https://youtu.be/FoNLQvf4NUs
In case someone wanna review calculus 2

[tall mortar]

Can someone please help with this problem?

I can't figure out what the interval of proportions would be for the population size of 340 that would still have a margin of error of 0.05

To find the population sizes I've been using the formula of n=p(1-p)*((1.96/M)^2)

[left knoll]

integrate (3x+1)e^(3x) dx

can someone help me with this??

[left knoll]

By parts

[left knoll]

yuss i know but can you find the answers please

[left knoll]

thank you

[frigid violet]

… I’m so stupid-

[flat bolt]

I dont know any simpler methods but heres my explanation

[silk quiver]

i got 1/6

[frigid violet]

Same. I got 1/6 too. But what if you double it. Like make it 2 x 4

[silk quiver]

then the height will be double and the base will double making it A=1/2bh = 1/2 * 2 * 2/3 =2/3

[frigid violet]

Oh right, I’m so stupid. Thank you so much!

[quasi nova]

Hi guys how to learn calculations faster.. suggest me some ideas

[fair lion]

the 17th term of an AP exceeds its 10th term by 7. find the common difference. (ik its 1 obvio but idk the method yet..)

[cosmic goblet]

@fair lion

[fair lion]

thank you! :).

[cosmic goblet]

got it ? My handwriting xD

[fair lion]

nah got it...

👍

[random flame]

Hi can someone help me with this? Ping if you do and thanks!!

[silk quiver]

y = -2x^2 + 2x + 7
y = -2(x^2 - x) + 7
y = -2(x^2 - x + 0.25) + 7 + 0.5
y = -2(x - 0.5)^2 + 7.5

[hidden basin]

Can anyone here help me with limits in calculus?

[silk quiver]

i can try. is calcu shortcut allowed?

[hidden basin]

maybe

i’m not sure if the answer i have is right or not

[thick pine]

Looks good to me

[thick pine]

https://en.wikipedia.org/wiki/Completing_the_square

[hidden basin]

it was, thanks! I just wanted to be sure because i really need this 100 lol

[silk quiver]

yeah i think it's right

[hidden basin]

I’m stuck on this one, can someone help me pls?

[silk quiver]

i think they're all -6

[hidden basin]

oh that makes sense

[thick pine]

correct

[random flame]

Ah thanks! I actually know the answer but I forgot how to make the equation into a completing the square form 😅

[viral estuary]

ayo anyone whos good at math and can do year 10 igcse stuff please dm me asap

[quartz cove]

can someone help me with this question please.

Find the absolute and relative increase in lateral area of a blood vessel
A = 2 πRL, with radius of the lumen R = 1mm, and length L =5 mm, given that the
change in radius stands at ∆R = 0.1 mm, change in length ∆L = 0.002 mm.

[stuck mauve]

Anyone know how to do?

[elder mist]

@stuck mauve is the answer 432?

it should be 5.76*75=432

as standard deviation is not affected by the (-100).Standard deviation remains constant unless you multiply or divide something.. Subtraction or addition has no effect

[stuck mauve]

That’s what the answer key said

Oh yeah, that makes sense. Thanks

I definitely overthought that

[elder mist]

yeah..if they wanted the probability distribution ,it would be (19.25*75)-100

[analog kettle]

limit is -6 both from right and left side at 2 i guess from the graph

[analog kettle]

fill all the four blanks with -6

[solar pilot]

i dont even know how to start this

[analog kettle]

isnt the angle H = H' ?

[solar pilot]

i think it might be to me h looks like k

which is 50

[autumn dune]

If the triangle is only reflected, that means the angles are unchanged

[solar pilot]

oh ok sorry

[autumn dune]

So H = H', K = K', G = G' (where i noted "H" = "internal angle at H" etc)

But you (should) have a theorem saying that : "The sum of the angles of a triangles always add up to 180°"

[silk quiver]

so that just means H' is 40?

[autumn dune]

You know one angle : K = 50 °
And you know another one : the right angle at G
According to our theorem :
K + G + H = 180
meaning
50 + 90 + H = 180
by substacting successively 90 and 50 on both sides, we get
H = 40
but H = H' !

[solar pilot]

tysm

[autumn dune]

(:

[pliant drum]

Hey, can someone explain me how to prove that this limit doesn't exist, by taking two paths that gives you different results?

(I don't know if these are the actual english terms but I think you understand : s)

[left knoll]

how to find the range of real function: |x-4|/x-4 (the ans is {-1,1})

someone pls help ;-;

[somber hemlock]

|x-4| can be two values. One (x-4) when x>4 and second -(x-4) when x<4

[pliant drum]

https://www.youtube.com/watch?v=a0i9Xos9LVg

[somber hemlock]

Yeah basically this only

[pliant drum]

I don't know what is that language but I hope it helps

[somber hemlock]

Doubtnut is an indian website.. so ya it is in the indian language

[left knoll]

ohh thank you everyone for your help!! I've understood it now :) thanks!

[latent siren]

You still there, first, try to look at the path x=pi, and take the limit as y approaches 1. What do you get?

[dawn crypt]

How do i integrate y=240sin(2t)

[pliant drum]

0/0, denominator equals 0 and cos(pi) = -1

[latent siren]

Use sin(2t)=2sin(t)cos(t), then let u=sin(t)

[thick pine]

Is anybody good with vector analysis?

[latent siren]

No, the limit is 0.

When you are in the line x=pi, the function is always 0. So when you take the limit as y-> 1, you get 0.

[pliant drum]

Oh, okay, that makes sense

[latent siren]

So you have one path that evaluates to 0. Next, try the path x=-arccos(y), and let y->1 (from the left). You see then that your input approaches the point (pi,1).

[dawn crypt]

hmm ty

[latent siren]

I made a mistake, use the path x=arccos(-y), then evaluate y-> 1.

Also you should know that y^2+y-2 = (y+2)(y-1)

[pliant drum]

OHHH

that gives me 1/2

okay, that helps a lot, thank you ❤️

[dawn crypt]

hmm idk

the answer should be -120cos(2t)+c

and integrating sin results in -cos right?

or is this composite function?

[pliant drum]

let 2t = u, and integrate in in terms of u

change your dt to du

u = 2t
du = 2dt
dt = du/2, plug that and integrate sin(u)

[dawn crypt]

right, thanks

got it now

[pliant drum]

np : s

[thick pine]

Can anybody help me, I have absolutely no clue... I roughly translated the text so sorry for any mistakes

@latent siren I heard you're doing a PhD in maths, maybe you can help me 🙃 😫

[dawn crypt]

😳🙏🏼 praying for you bud

[north temple]

lmfao

ikr

[thick pine]

😆

[dawn crypt]

anyway

[north temple]

think you just have to integrate it

[dawn crypt]

Where does the 260 come from

[north temple]

yeah

let me see

you have to find the c

the c is 260

basically when you get the velocity by integrating the acceleration, you still have to get the c term, thats why he gave you the speed

c = 140 + 120

you get me?

[dawn crypt]

yeah i get the integration part

but rn hella confused about the 260

i get 140 is starting velocity at t=0

[north temple]

do you know when you integrate you have to add a (constant) that you dont know the value of

[dawn crypt]

yeah

[north temple]

yeah basically he gave you the t = 0 and the value of speed to get that constant

[dawn crypt]

oh wait

tf

140+120cos(0) = 260

thats it

[north temple]

yes

[dawn crypt]

im hella dumb

gawd damn

[north temple]

it's ok

[silk quiver]

also you can check at t=0 velocity is 140 to make sure your expression is correct

[dawn crypt]

😔 🔫

[manic tartan]

can anyone here help me with probability and statitstics

[thick pine]

Just ask maybe somebody knows something

[latent drum]

Hi, guys I'm looking for someone who can prepare for SAT/TOEFL IBT with me. If anyone is interested you can message me directly here or at instagram: edushab_ and then I can introduce myself and tell about myself so you can make a decision

[silk quiver]

we can try

115

opposite angles of a quadrilateral are supplementary

as long as it's inscribed in a circle tho

[thick pine]

Damn the things you guys in the US learn in school are crazy

[bleak tree]

anyone who can help with NCERT syllabus for grade 10 th? , react or reply

[thick pine]

Maths is so different from the stuff here in germany, it's crazy

[latent siren]

I'll go back to it bud. Lemme just get my coffee.

Daaaamn, this is analysis stuff. Do you have a higher resolution image? I cannot read the bounds on the partial derivatives.

[thick pine]

Alpha1 and Alpha2

Like in, derive alpha1-times for x1 and alpha2-times for x2

[latent siren]

Ah, I get it. This is hard, I don't know if I can figure this out tonight hah.

Hess_0(f) is the Hessian evaluated at 0?

[thick pine]

Yep

[latent siren]

Usually you can get bits of hints within the lecture. What were you studying before this? Maybe you were given a crucial theorem within the class?

[thick pine]

They teach this stuff in 2nd semester of university here 😁

Wait I can send you the script

[latent siren]

sure

no guarantees that I can do this though lmao

[thick pine]

https://home.mathematik.uni-freiburg.de/ngrosse/teaching/Vorlesungen/AnalysisII/Analysis2_SS-21_Skript.pdf

It’s in german though but maths is universal right

[thick pine]

1.7 should be the relevant part

[silk quiver]

5

FH * JH = EH * GH
4 * 10 = 8 * GH
GH = 5

[agile sail]

can i get some help with this

[silk quiver]

50%
12.5%
25%
87.5%
no, because red has 25% probability and if you spin 80 times, it should land red about 20 times@agile sail

[latent siren]

Sorry man, I can't read German (yet). I don't think I can do the problem. Seems like a lot of it is topology though. I have a feeling that this has something to do with generalized Taylor's theorem (i.e. for dimension n=2).

[silk quiver]

100

[agile sail]

thanks a lot @silk quiver

[thick pine]

Yes that's what my tutor also recommended but I am completely lost - to me it seems like the variable p is in there far too often

[latent siren]

So, the thing is that, you can probably approximate f(p) by expanding near 0. You can probably control the bounds using the hypotheses given to you. Seems like a lot of work though, and... I still have research to do tonight.

[thick pine]

If D_p f = 0, aren't all the partial derivatives 0 automatically? Because then the 2nd part with the root makes no sense

[latent siren]

Wait, is p a specific point?

Or is p any point in the closed ball?

[thick pine]

Don't worry about it 🙂 If you have time, I can still solve it until wednesday, but it's fine otherwise

[thick pine]

That's what I dont understand

I mean it says it's some point in the ball

[latent siren]

This is not neatly posed. Maybe you can ask the instructor?

Cause p was only invoked to be in the ball later in the question

[thick pine]

Exactly, that's what's confusing me too. It feels like there should be D_q f for some q in K or whatever

I'll ask her tomorrow morning

[latent siren]

So anyway, D_q is the total derivative right?

Just so we're clear.

[latent siren]

Because this is not true if you mean total derivative.

[thick pine]

By D_p f I mean the total derivative

[latent siren]

Okay, so the total derivative is pretty much the sum of partial derivatives, if the sum of the partial derivatives is zero, then it does not necessarily mean that all the partial derivatives are zero.

[thick pine]

But that’s a 1x2 jacobi matrix right?

[latent siren]

Ahhh, I see you defined it to be the Jacobi matrix.

[latent siren]

Ahh, okay I get it. The zero total derivative means that the first order partial derivatives are zero. But the bounds are talking about third order partial derivatives.

Recall that f'(x_0)=0 does not mean that f''(x_0)=0 as well take for example the function $f(x)=cos(x)$ at x=0.

[latent siren]

Seems like I'm wrong, eep.

[thick pine]

Ahh, thanks I missed that!

[pliant drum]

oh, since we are talking about partial derivatives...

So, I have this top equation that I had to calculate the partial derivatives (Zx, Zy, Zxx, Zyy and Zxy) and now I haveto use them to calculate the bottom total derivatives. Any clues? I think it's something with the chain rule, but I'm not getting any closer to ):

nevermind, think I got it ( :

[thick pine]

Not e^x x^{e^x -1}?

[velvet terrace]

The location of S is (-4, -4) but I don't see that answer choice there. The distance between point A and point T is sqrt (10) = 3.16227766

[wintry violet]

ohhhh

if it is a degree measure of arc

then are you right

[wintry violet]

actually Q isn't center of the circle

[left knoll]

Yeah, it is not so we don't say 100 degress

İ think the answer is 67

[velvet terrace]

you right

[wintry violet]

it will be like so

we can find angle MQP

and then 180-MQP

or wait

[left knoll]

That angle P can't be 34°.

İt is 17°

[wintry violet]

yea

and PMO = 50

my bad

[left knoll]

Yeah

[wintry violet]

67

[left knoll]

The sum of 2 outer angles returns an internal angle

So it is 67

[velvet terrace]

yes

[left knoll]

Yeah, it is so

[wintry violet]

so i just proved it

[left knoll]

And this is formula but i dont remember this

[left knoll]

Yeah i agree with u

[coarse rose]

hi

u know how to use octave?

[frigid violet]

Uh, I need help with question 3

[fiery haven]

uh i don't know for sure but i think it's e because theyre asking for the interior angles of this combined triangle-square-pentagon polygon and an equilaterial triangle has 180 degrees total, square has 360, and pentagon has 540, so 180+360+540=1080, and 6*180=1080. idk for sure but that's my guess!

[left knoll]

have you tried asking siri?

[fossil needle]

you right

[candid rivet]

by decomposing the square into 2 triangles and decomposing the pentagon into 3 triangles you get a total of 6 triangles, so the sum of the interior angles of the polygon is 6 times 180°

[teal karma]

Is proofing reciprocal identities difficult or am I stupid

[hollow escarp]

There is a general formula for any polygon , That the sum of all interior angles is (n-2) * 180. Here , the number of sides n is 8. So, sum of the interior angles is (8-2) * 180 = 6*180.

[hollow escarp]

@frigid violet . The basic concept behind this is what @candid rivet said. We break down the polygon into triangles and multiply by 180. if a polygon has n sides , the number of triangles it can be decomposed to is n-2

[frigid violet]

Thank you so much! Both of your explanations are super helpful! Thanks!

[frigid violet]

Thank you!

[thick pine]

Ah damn there are multiple typos in the text. First p should be 0 (so D_0 f = 0), and the variable we're looking for should be q in B_2(0). That makes much more sense for the Taylor series around 0

I'll try solving it but I'm still not sure if I can do it haha

[restive kraken]

anyone is free? i need help in this. intergration topic...

[thick pine]

V = pi * A

[thick pine]

So step one would be to find the area under the function

Do you have an idea how to get the area?

[bronze edge]

Could anyone help me with number 15? The awnser os 1/3 but i don't understand how to get on it

[left knoll]

Gotta rationalize the numerator

[bronze edge]

I did that but still the result i got was 1/2

[left knoll]

Try Photomath

[bronze edge]

Why in that case i have to multiply by ∛(x+1)² + ∛(x+1)+1 /[∛(x+1)² + ∛(x+1)+1]?

[minor sluice]

Lmao I got a test on this tomorrow

[latent siren]

I think I have a sketch. Now, look at the following article: https://en.wikipedia.org/wiki/Taylor's_theorem#Taylor's_theorem_for_multivariate_functions

Look at the first summation, ignore the remainder terms first. You have all the information to estimate the first summation.

The hypotheses say that at the point p=0, the first order partial derivatives are zero, the hessian says the values of the second order partial derivatives, and an estimate about the third order partial derivatives are given to you.

[restive kraken]

wait can you use the intergration method?

[robust prism]

anyone can tell me how to build equation for this and tell me reason

please

thank you so much

[thick pine]

That gives me x^2/2 + 2xy + y^2/2 + 1/(2sqrt(2)) when I use the estimates

[thick pine]

Yeah you can integrate the function to get the area, correct

[restive kraken]

can you show me how?

[silk quiver]

6.80 + 0.90x = 7.30 + 0.65x
0.25x = 0.5
x=2

[thick pine]

You need to find the integration bounds first

as in, where does the graph meet the x axis?

[bronze edge]

You want to find which one is followed by x and which one is not followed by x -the constant.

[charred marsh]

Can someone help me?Name 6 numbers that, rounded to the nearest hundredth, add up to 7.83

[restive kraken]

0 and 2?

[thick pine]

Yes correct so now you have the bounds for your integral

[restive kraken]

so i just can find the volume by finding the area first? because i was a bit confused when the question ask towards the y-axis

[bronze edge]

In that case, you will always buy a large pizza, so, the constant is the price of the large pizza and the toppings are relative to how many toppings you want, so they are followed by x

[thick pine]

I think it doesnt matter which axis it is

Not 100% sure though

[restive kraken]

oh it's okay. Ty for your kindness

[thick pine]

No problem I hope it helps

[charred marsh]

Can someone help me?Name 6 numbers that, rounded to the nearest hundredth, add up to 7.83

[latent siren]

Now try to use the fact that (x,y) is in B_0(2)

Maybe you'll get something like |f(z)|<1, which means -1<f(z)<1, then you're done.

[thick pine]

But I don't know how close the taylor actually is to my function right

[latent siren]

actually after you get the estimates, try to let (x,y) -> (0,0)

[thick pine]

😳

[latent siren]

your remainder will go to 0 as well.

So in the end, p=0

I'm not sure if this will work though.

You're basically approximating f(0) here, and we'll try to show that -1<f(0)<1.

[thick pine]

But of what use is this if I have to find a q with f(q) < -1

[latent siren]

That's what I'm wondering too. It's technically true that 0 is in the ball, but I'm not sure about finding a particular q in the ball.

[thick pine]

Maths is too hard for me 🙁 😆

[latent siren]

Is this for a graduate class?

Seems like too estimate heavy for an undergraduate class

[thick pine]

It's 2nd semester undergraduate, B.Sc. maths

[robust prism]

Noice

[charred marsh]

Can someone help me?Name 6 numbers that, rounded to the nearest hundredth, add up to 7.83

[robust prism]

This is a nice grup thanks everyone

[bronze edge]

no problem!

[autumn sorrel]

Can anyone help me with advanced statistics?

[white sierra]

if f(x)=0.5x does this mean that F(x)=(x^1.5)/1.5?

I'm trying to figure out the primitive function of 0.5x

[supple island]

F(x) would be (x^3/2)/3 +c

[white sierra]

Wouldn't that look like this?

I end up with 0.5x^1.5

I don't know how to get rid of the ^1.5

[supple island]

x^(3/2 -1) is definitely not x^(1.5)

it's x^(1/2)

which is x^(0.5)

thou i suggest using fractions rather than decimals with exponentials, it's much easier

generally decimals are very "ugly", fractions are much easier to simplify

[white sierra]

Ooh I see my mistake. Using decimals has given me the wrong answers several times so I'll take your advice and to start using fractions. Thanks for the help <3

[supple island]

np 😉

[white sierra]

The question is literally rigged

Question 6. It says "The figure shows y=f(x). Calculate the integral from 2 to 6 with the help of the figure"

You're meant to be able to do it without a calculator...

The super easy way would be to split it into a square and a triangle but how do I do it using the actual integral?

[thick pine]

f(x) = 1/2x + 2

Integral from 2 to 6 is F(6) - F(2), and F(x) = 1/4x^2 + 2x

@white sierra

[olive marten]

completely stuck on this, anyone have an idea?

[thick pine]

So 1/4 * 6^2 + 26 - (1/4 * 2^2 + 22)

= 21 - 5 = 16

[olive marten]

Urgent please help

[olive marten]

Omg u found the ms

Thx so much

[novel sonnet]

Is this an exam?

[olive marten]

No it’s homework

[novel sonnet]

Ok 👍

[olive marten]

My prof said that it was the hardest question in one exam

[novel sonnet]

Quite an interesting result isn't it

[merry coral]

J cole, all of a sudden so good at math ?

kiss me now

[novel sonnet]

This integral tells us that 22/7>π and it also approximates pi to five decimal places

[agile sail]

can someone help me with this question if you don’t mind

[fiery haven]

well basically correct me if im wrong but i think what you have to do is find the probability for each event and then multiply it together. so like the probability of getting 4 is 1/8 since there are 8 separate choices in the spinner and the probability of getting c is also 1/8 and 1/8*1/8=1/64

that's for question 1 btw

u can do the same with the rest

[agile sail]

thanks for your help

[spring sphinx]

pyth theorem

[robust prism]

Can anyone tell me the minimum point of question c

Before modulus it

[silk quiver]

Just set y=0 that will be the minimum points of parabola in absolute value. In this case, 2x^2 +5x -3 = 0. That will give us x=-3 and 0.5. Therefore the minimum points are (-3, 0) and (0.5, 0)

[silk quiver]

the shortcut is to do the rise over run method since there is a graph available

the proper way would be this

[left knoll]

May someone help me with some trigonometry homework?

Dm me if you can

[analog token]

damn

this actually a worksheet or a hw

[lean hearth]

hey guys, I'm currently conducting a survey for my statistics class involving time spent on phones and school performance. it's completely anonymous and open to all ages. i'm really interested in this subject as I was previously severely addicted to my phone. thanks everyone https://forms.gle/C35RNUHkWmuEPf666

[robust prism]

but this is actually find the x intercept

minimum point need use some completing the square method

[silk quiver]

x intercepts are the minimum points of parabolas in absolute value

y can't be negative

[silk quiver]

that is if the expression is not in absolute value. the lowest point will be the vertex

[silk quiver]

here is the graph with and without the absolute value

[white sierra]

thank you!

[ancient pasture]

any german people here who can help me with some maths?

[thick pine]

Yes

[thick pine]

No problem I hope it helps

[ancient pasture]

i already got some help from a classmate but thanks :D (nächstes mal, wenn ich wieder am verzweifeln bin, meld ich mich :D)

[thick pine]

Okay sure (Mach das gerne ☺️)

[random flame]

Hi can someone help me with this? I have to find the area of the triangle. Ping if you do and thanks!!

[supple island]

that seems a right triangle

do you know what height is in a triangle?

[dawn girder]

i don’t think it is, doesn’t obey pythagoras’ theorem

[supple island]

idk, can't read the numbers

[dawn girder]

I would check out heron’s formula 🙂

[random flame]

You mean the one that goes smtg like 1/2(b)(c)sinA ?

[dawn girder]

Nope, it’s one that gives the area of a triangle given the length of all three sides

[random flame]

Erm don't think I have learned that yet

[robust prism]

ooo thank you so much👍

[true nexus]

hey could anyone help w 71

all I really need help w is figuring how to set up the equation

[supple island]

(2(x+h)+1-(2x+1))/h

then do the limit for h->0

[true nexus]

ohhh oki tysmm

[supple island]

generally if you modify the argument of the function (ex. from f(x) you go to f(x+2)) you only modify the argument ( so if f(x)=3x+5, f(x+4)=3(x+4)+5 )

[slender vault]

Could anyone tell how to do the b part

[true nexus]

ooo I see tyy

[hearty sandal]

Hello, can please someone explain me how i go from the first to the other plz

[bronze edge]

Sorry I'm since yesterday trying to understand but I can't :/

[chrome marsh]

This formula is to calculate the distance you are from a lighthouse (from a boat), I have no more information than this, are the formulas the same? I understand that I can use one or the other, right?

[left knoll]

Hello!! does please anyone know how to solve this?I'm happy for any advice. Thank you!

[supple island]

consider that every dimension of the model is reduced by 50, and area is given by multiplying 2 dimensions

[supple island]

they are the same formula

[left knoll]

thank you for the hint!

sorry does someone know how to do this?- ive been stuck on this for a while

[silk quiver]

That aint the graph of the equation

The center should be at (1,2) with radius 4

[left knoll]

oh wait ive been doing this all wrong, thank you @silk quiver !!

[crude zealot]

can anyone help me with a math that needs thevenin resistance>

Message #tech-related-help

[chrome marsh]

good math question, I don't know how to solve this variable

[bronze edge]

I think it was just some kind of theory that's why was deleted ||/j||

[woven orchid]

A company makes umbrellas. Each parasol is sewn together from eleven equal parts, and the parts are cut out in the shape of a circular sector. The radius of the sectors is 115 cm and the degree is 30 °. Find the area of the circular sector.

how do i find the area?

[supple island]

to find the lenght of a sector of a circle you have to multiply the angle of the sector in radiants by its radius

[chrome marsh]

I'm bad at trigonometry, How can I know the angle alpha? I think that it's tanAlpha=h/d? If so, then how do I separate the angle from the tangent?

[woven orchid]

In radiants?

[silk quiver]

calculate first the area of the full circle using pi*r^2 that's the area of 360 but since you need only 30 deg you need to divide it by 12

[woven orchid]

oooh ok i understand, thank you

[supple island]

which is the same thing but it doesn't apply to all cases

[bronze edge]

There is no way to separate the tangent from the angle, you need to find the tangent of alpha then look up in a table to know what is the angle if i'm not wrong

[silk quiver]

that's basically the formula of sector tho so it applies to all A = pi*r^2 * (angle/360)

[chrome marsh]

Perhaps he has left me something or does not understand it, the good thing is that I have found another formula that allows me to get what I need. Weird things from boats and lighthouses, but thank you very much

[north temple]

Can you explain how did you solve it

Because I don't get what's happening there

Isn't tan alpha equal h/d how can it be h*d like they gave

[silk quiver]

you're welcome invincible

[woven orchid]

😮

[silk quiver]

waiting for season 2

[woven orchid]

Yeah same. Season 1 was really good.

[silk quiver]

yeah it also triggers me because d should be h/ tan (alpha)

[chrome marsh]

Another thing may be that I was wrong in stating the problem

I start over just in case. I have the height of the lighthouse (h) and I have the distance to its base (d), I need to know the angle (I don't know very well because since the distance is what interests me in this problem)

I already say that trigonometry is not my thing, so from my logic tan(alpha) is not the same as (alpha), or am i wrong?

So what interests me is, having tan(alpha) obtain (alpha), I imagined that maybe with the arctangent o some shit like that

[north temple]

Yes

Tan alpha isn't alpha

Idk about the last part

[crude trail]

it is only if alpha is a small value

[bronze edge]

that's right

[north temple]

I don't think I understand the question though, what does he need

[silk quiver]

yeah to obtain alpha. just use arctan(height/distance)

[north temple]

did he not give any numbers?

[chrome marsh]

I imagine this because (example): tan alpha= 0,587347, in the calculator if I press Shift tan of 0.587347 {tan^-1 (ans)}=30º25´40´

[north temple]

yes

thats it

[chrome marsh]

Thank goodness, It was driving me crazy

I hate these conversions when I have to operate with arctan, arcsen, cosec, cotan ...

thanks you all for trying to understand me hahahaha

[bronze edge]

No problem c:

[red spruce]

I have a question can't solve it someone help

PS. Equations of circles type

[silk quiver]

shoot it

[red spruce]

5th one

[hearty sandal]

I might be dumb but i can't see how we went from line 1 to line 2

[rain gorge]

n factor

distribute the n in the second line

[weary arrow]

basically, they've put the n in front of the parenthesis to show both parts of the equation includes one n

idk if that made any sense

[rain gorge]

exactly

[hearty sandal]

thx a lot !

[left knoll]

@red spruce hi another jee aspirant

[silk quiver]

if you want the center - radius form it is (x +2/7)^2 + (y-41/7)^2 = 1300/49

[chrome marsh]

How good are you with vectors and trigonometry? I have another question about boats

[silk quiver]

here is the graph for checking

[silk quiver]

shoot

[chrome marsh]

Leave me a moment that I am preparing an image in paint so that you understand it as well as possible

[red spruce]

Thnx

[red spruce]

Line point form of family of circle man I should've thot bout this smh

[rain gorge]

I solved it and got the same results but in a different method

the numbers looked silly though so i thought I was wrong

I mean 1300/49

for real?

[silk quiver]

if the answer is in big fractions we always doubt our answers that's why it's better to have tools like online grapher to double-check

[red spruce]

Pretty straight forward if you don't mess up the calc

@rain gorge

[rain gorge]

I did it differently

I am not familiar with Line point form of family of circle

that is prolly why

[red spruce]

What was it

Well one thing we can do is take the general eqn of circle, satisfy it with both the points nd then consider tangential distance as radius to get three relations with three variables g, f, C but its very tedious and Calc mistake

[woven orchid]

determine the perimeter of the square ABCD exactly.

I know that i need to find AD, but how?

[rain gorge]

@red spruce that is pretty much what I did yea but I used the perpendicular lines equation

[woven orchid]

Wait, nvm its pretty easy

[red spruce]

Isn't that how u find radius from tangent that's what I said

But this approach is tedious

[rain gorge]

That is true

[red spruce]

:)

[silk quiver]

find the length of DB first using cosine law then another cosine law to find the length of DA

[chrome marsh]

I had prepared 2 images explaining everything but in the meantime I have realized where the problem was, so for now there is no need for help with vectors hahahaha

[red spruce]

Cosine law is pretty useful everywhere ngl!!!

[woven orchid]

Yeah i thought of that too. Thank you though!

[chrome marsh]

in the study room 13 we don't believe in the cosine law

[wooden spade]

does anyone now how to get r^3 from the equation above?

[median juniper]

im completely lost w this question haha :

You deal two cards at random from a 52-card deck simultaneously. What is the probability that the total of the cards is more than 3 and less than 12, if aces count as 1, twos are 2, threes are 3, etc., and face cards are 10?

[iron void]

---

The final grades in a math class have a mean of 72 and a standard deviation of 5.43. If the professor plans to give an A to the top 7​% of the​ class, what is the cutoff for an​ A?

could someone help me understand this ^^^ please

[round rampart]

helppp

[sullen lantern]

the coordinates of the center of the circle will be (2,-1) as it is a circle (equation (x-h)^2+(y-g)^2=r^2 with center, (h,g) ) and the radius will then be 13/2 as the right hand side of the equation is r^2, so taking the square root we have 13/2 as radius cannot be negative

[sullen lantern]

i don't think so :( it's been a long while since i've done questions like those

yep no problem

[marble gale]

Help me with this plz!

[twin bolt]

Ayo can anyone help me with this?

[silk quiver]

=2 log2 3 - 4 log2 3
=-2 log2 3

[twin bolt]

Do you mind me asking how you did it?

If not that's completely fine haha, thanks for the help though

[silk quiver]

The distance of center to the chord is (13/2)^2 = (6)^2 + d^2

[silk quiver]

log x^n = n log x

[left knoll]

Hmmm, I need linear algebra help

I can't figure out how to solve the wronskian.

[urban berry]

Hello everyone!) I have a problem with this third-order nonlinear ordinary differential equation...

Can you help me please🙏

[sullen lantern]

hm its been a while but when taking the derivative if cosh(7x) and sinh(7x) it should be 7sinh(7x) and 7cosh(7x)? i could be wrong though, then using the wronksian, you would write those below each other, and taking the determinant you would get
cosh(7x)*7(cosh(7x)-sinh(7x)7sinh(7x) you would get 7, and since w(x) is non 0, that means it is linearly independent

i could be wrong thats just my thought process

[queen thistle]

hello, could someone help me please. How do I find the reference angle of -5pi/12?

[hearty sandal]

Hello, can someone explain how we go from the first to the second

I suppose that's u'/u = ln |u|

so it gives us 2 x ln (x +1)

but where does the + of the (2/x+1) come from

F(b) - F(a) seems to be the answer but i don't get it

[thick pine]

2(x+1)^(-1)' = -2(x+1)^(-2)

You have 2/(x+1) which has negative exponent, so if you differentiate it the sign changes

(The same but backwards if you integrate, like here)

[hearty sandal]

Thank you !

[woven orchid]

The perimeter of the figure is 16. What must the sides of the two squares be in order for the area of ​​the figure to be as small as possible?

[woven orchid]

Thank you so much!

[queen thistle]

can someone help me find the cosine equation for this graph please

[urban berry]

Does everybody know how to solve this differential equation? I know that it is Bernoulli’s eq

[tacit sun]

Can anyone help?

[safe ruin]

desmos OP

[tacit sun]

Thank you so much @silk quiver ❤️

[slow moat]

So basically I passed my exams because I watched this guy. https://www.youtube.com/channel/UCEWpbFLzoYGPfuWUMFPSaoA

[queen thistle]

Thank you very much @silk quiver

Can someone also help me understand this problem please.

[slow moat]

Have you worked with Quadrants before?

[queen thistle]

yes, i think I do remember

[slow moat]

Aight, I'll find my math notes, until then someone else might answer your question.

[queen thistle]

thank you ^^

[queen thistle]

how would that look like in fraction form?

[slow moat]

@queen thistle Also check out this guy if you still have difficulties understanding a topic. https://www.youtube.com/channel/UCEWpbFLzoYGPfuWUMFPSaoA

[silk quiver]

56/65

[queen thistle]

thanks guys!

[twilit wasp]

hello

could someone help me with this sum

[restive oasis]

anybody familiar with some complex numbers stuff?

[maiden sigil]

I never really understood cubed root radicals

[weary arrow]

2*3sqrt(7)

[urban berry]

Thank you very much!!!!💚💚💚💚💚💚💚💚

[merry sentinel]

Yo wassup

Help here

I accept step by step solution

@tribal bison

You sound like a math boi

[silk quiver]

how come x is 8 if 3.2^4 - 7.2^2 = 53.0176

[queen thistle]

hello, can someone help me out on this question please ...

[silk quiver]

it's sin(-15) or sin(345)

[queen thistle]

how is the calculation?

[tranquil tendon]

-0.26

[plain terrace]

Put a equals to 2^x/4, u will get 8

[plain terrace]

I will send u the solution just wait a minute

[silk quiver]

that (-pi/12) means that the angle is in radian just set pi to 180 to get the angle in degrees. in this case, sin(-180/12) = sin(-15)

[queen thistle]

how would it look like in radical form

or is it not possible?

[silk quiver]

(-sqrt(6) + sqrt(2))/4 @queen thistle

[queen thistle]

may I please see the step by step calculation for this please

sorry I meant in the calculation to find it in the radical form. But thank you for that answer ^^

[silk quiver]

ohh, so . there is multiply not decimal

[plain terrace]

Yup I hope I did it right

[queen thistle]

how did you get that radical form?

[silk quiver]

just type sin(-15) in calcu and it will show up

[silk quiver]

aren't you allowed to use calcu?

[plain terrace]

Correct me if I m wrong

@queen thistle

[queen thistle]

Thank you 🙏 @plain terrace @silk quiver

[plain terrace]

Is this a right answer, it's completely fine if I did wrong u can say it

[queen thistle]

no no, I'm confused on how @silk quiver got this answer, but they do have the same value. I jsut want to see the work

[plain terrace]

He mentioned the value of sin(-15) directly using calculus

[woven orchid]

How do i find ED?

[silk quiver]

can you translate it in english? because i got confused on AD = 9,6

[woven orchid]

Yeah, it says that AB=13, AC=12 and AD=9,6. Just forget the other stuff like "ovenfor"

It only says that the figure on top

[silk quiver]

what's the 6 for at AD=9,6?

is it like 9.6 like the decimal?

[woven orchid]

Yeah

9.6

[silk quiver]

oh ok ok i'll try

[woven orchid]

Thank you so much! You are really good at math 🙂

[plain terrace]

Well done brother ❤️😀

[woven orchid]

Yeah ^

[silk quiver]

you're welcome. just save us from omni-man😆

[woven orchid]

Hahha i will

[undone vapor]

is this correct

I need help

I suck at math

[silk quiver]

you're right

[undone vapor]

OMG

TYSM

is this negative or positive because I think it is positive

[silk quiver]

what do you mean by positive or negative?

[left knoll]

It’s positive

Negative would be upside down

[queen thistle]

excuse me, could some help me with graphing this please

[fringe kite]

do i simply substitute w(t) for 3 and solve for t?

[lavish jungle]

the real part of complex numbers represents x coordinate and imaginary part represents the y coordinate.

[lavish jungle]

no, w(t) represents radius at any time while the question is asking time at which the radius is increasing at a rate of 3. Therefore first differentiate w(t) wrt t and then equate the differentiated equation with 3 to get the time

[fringe kite]

sheeeesh thanks

[quartz finch]

same

[queen thistle]

Hello, I have a quick math question

what is the modulus of 75

does it have one or does it stay the same value?

[near acorn]

75

[queen thistle]

i do not need to use this equation at all?? for some reason I am scared its a trick question at first I thought it would be like 1 (which I doubt)

[near acorn]

If you want to calculate the modulus of a complex number z where z=a+ib then yes you would want to use that equation

The modulus of a real number is basically the absolute value of that number

[reef timber]

the modulus is geometrically the distance from a point to the origin O. So if the point is on the axis it basically doesn't change. You can see it as that.

[random flame]

Hihi can someone help me with Q1bi? Ping if you do and thank you!!

[frail nova]

Hmmm
If you guys right the question in a another way i can solve it

[random flame]

As in?

[candid rivet]

you can do it by applying the cosine rule in the triangle PRQ

[frail nova]

Give me a time to think im not good at sine cosine

[random flame]

You mean a^2=b^2+c^2-2bc cosA ?

I tried that but I got the wrong ans

[frail nova]

Sorry i cant help

[random flame]

Issokay ^^

[candid rivet]

yes, you have : RQ²=PQ²+PR²-2PQ×PR×cos(38°)

[candid rivet]

and then you just take the square root of it

[frail nova]

Wooow

Nice job

[random flame]

Hmm

[frail nova]

Couldn't think if that

[random flame]

Thing is I did that, but I got it wrong

[frail nova]

Lemme try it

[random flame]

Hold on lemme send my working

[candid rivet]

i get RQ=201,5

[candid rivet]

thanks ^^

[random flame]

😅😅

Idk what I did wrong

[candid rivet]

the first line looks ok but then i donc really know what you did

[random flame]

PAHAHA OOPS-

Thanks btw XD

[frail nova]

-2PQ
You mean -PQ²?

[candid rivet]

but just grab a calculator it's easier haha

[candid rivet]

no problem :)

[candid rivet]

no it is -2×PQ×PR×cos(38)

[random flame]

I literally have a calculator with me and I'm just screaming how can I still get the same wrong ans

[frail nova]

Sorry im not good at math not used to handle these math problems

[candid rivet]

if you copy the first equality you wrote you should get it right i guess

[random flame]

I’m still getting the same thing 😂

OH WAIT-

I GOT IT-

;-;”””

Again, thanks guys!! 😂

[candid rivet]

no need to apologize

[candid rivet]

Yeayyy !

[random flame]

Thanks y’all!!! TvT

[candid rivet]

you're welcome budy ^^

[vivid knot]

Nevest has N equilateral triangles. Nevest wants to arrange them into a polygon. He can resize or rotate each of the existing triangles. The triangles should not overlap and the polygons should be simple. Determine the minimum number of sides of the polygon to form.

hii can someone help me with this problem? im guessing there will be some formula to solve this problem

[silk quiver]

i'm guessing that if N is greater than 1 then the minimum number of sides of the polygon to form is 4

[hardy hare]

hey besties can someone help me with math LOL

[autumn sorrel]

pretty sure a triangle is a polygon

there needs to be a min of 3 sides and 3 angels for a poly to form

[autumn sorrel]

sure

whatsup?

[hardy hare]

its asking to simplify this is it right that the answer is zero

[autumn sorrel]

lol

what is it asking you?

[hardy hare]

to simplify a trig equation bestie

[autumn sorrel]

lol

I'll put it into chegg and see what it gives

havent done trig in yearss

[hardy hare]

rest in pisces

[autumn sorrel]

Give me a good rating on Uber

LOL

[hardy hare]

WHAT

ok anyway thanks

[autumn sorrel]

np I tried

[hardy hare]

it actually helpedLOL i was wrong thx thx

[left knoll]

Actually i think it can be the answer too

[hardy hare]

yeahh! thats actually the answer lololol

[left knoll]

That’s cool btw!!:))

[merry sentinel]

Bruh i thought it was decimal 3.2 and 7.2 😂

[plain terrace]

It's ok buddy , I hope my solution helped u

[merry sentinel]

Yeh i figured it out but thanks anyways

[woven orchid]

determine k so that the equation below has only one solution

[weary arrow]

one solution if 16^2 - 4k^3 = 0

so k=4

[robust prism]

For question 3 is the range of g
g(x)>/= 2?

[silk quiver]

Range: [2, +infinity)

[peak eagle]

it's right you can write it as you did or like Born did 🙂

[woven orchid]

how do i find the area?

[silk quiver]

find the length of CA 1st using cosine law
the quadrilateral will be divided into two triangles.
then just use heron's formula to find the area of each triangle then add it

[still flower]

lol I've been trying to do this without even hearing about heron's formula. u learn that in highschool?

find it weird i haven't learned it

[obtuse basin]

I haven't learnt it too

[silk quiver]

never heard of it in high school as well

[obtuse basin]

I just saw it in a textbook

[silk quiver]

only learned about it in college

[hardy hare]

HELP I REALLY NEED HELP RN PLEASE

[silk quiver]

shoot

[hardy hare]

HOW DO I MANIPULATE THESE SO THE eQUATIONS IN BOTH SIDES WILL BE THE SAME IM BEGGING

[silk quiver]

just moving left side? or right side?

[hardy hare]

WHAKTJHEAKHGK NO

[woven orchid]

i found that the whole areal of the figure is 1490

[still flower]

@woven orchid For A2 i also got 809.2, so something is wrong with A1 for one of u.

[silk quiver]

how come? because even if i don't round up the values, it still shows 1480.99

[woven orchid]

yeah i did wrong

[hardy hare]

THANK U LOL

[still flower]

@silk quiver watchu doing at college?

and where (edit: or are u done)

[latent coyote]

hello! may i ask how to factor an equation with a missing term?

[robust prism]

Thanks born sinner and patri🥳

[woven orchid]

O = 42.

How do i show that the area can be written as:

homework is hard 😦

[silk quiver]

what is the relationship of x and y?

what is O?

[woven orchid]

O is the perimeter to both triangles

i don tknow the relationship?

[still flower]

3x +3y = 42

[silk quiver]

ok ok so O is the perimeter of the whole shape

[woven orchid]

yeah

and its a it is a likesided triangle

[woven orchid]

oooh ok i understand now

its easy i am just dumb

[silk quiver]

just practice playing with formulas and you'll get better

[woven orchid]

Its so annoying that they teach us basic trigonometri, but then give is questions like these

[silk quiver]

yeah, that's why you always need a reference book. you won't survive with just their lessons

[left knoll]

guys i need help. where did this 12x came from?

this is the question

[latent coyote]

6 times x and then times it to two

[left knoll]

sorry i don't understand oof

it's supposed to be x square + 36

[latent coyote]

(6x)(2) or from FOIL method
First term: x^2 plus
Outside term: 6x plus
Inside Term: 6x plus
Last term: 6^2 = 36

[silk quiver]

foe better understanding

[left knoll]

omg thanks

this helped

i faced few questions like this and did not know where the values were coming from

[latent coyote]

you can use this for your other problems credits to the organic chemistry tutor :))

[left knoll]

okay i will :))

[silk quiver]

i'm studying electronics engineering in philippines

[still flower]

nice

[latent siren]

EEE UPD?

[left knoll]

Hi, can anyone help me with this?

[latent siren]

Do you know the quadratic formula?

You can use it to deduce that, without loss of generality, alpha = (b+sqrt(b^2-4ac))/2a and beta = (b-sqrt(b^2-4ac))/2a. Now you just compute the required expression using alpha and beta in terms of a,b,c for your problem. I think you should end up with something without radicals.

[left knoll]

Well, this is the solution to it... It didn't really require the formula as they just deduced it

[latent siren]

why do you think alpha + beta = -b/a ?

[left knoll]

Proof of alpha + beta = -b/a

[prisma heron]

Can anyone pls show me an example of deriving equations?

[hardy hare]

does anyone recall the equation for this lol

[rain gorge]

The last one is wrong

[proper sail]

a2 = b2 + c2 − 2bc cosA for finding the other side

[hardy hare]

amen thank u thank u

[hardy hare]

a would be x right?

[proper sail]

ans then sinA/A =sinB/B for the othet angles

[latent siren]

So we ended up using the quadratic formula to derive it

[left knoll]

Yes, but after derivation what will we do?

[woven orchid]

Do you guys know programing?

[final island]

which language?

[woven orchid]

english most likely

its math though

i got this program and when i run it, it gives me -2.0

[final island]

i meant programming language lol

[woven orchid]

python?

[final island]

yea that's python

[woven orchid]

i dont get what this program does though

[serene ginkgo]

@woven orchid i think for a it takes c + dx (2+0.000001) as the parameter for f(x) to return (0.5 x (2 + 0.000001)^3 - 2 x (2 + 0.000001)^2 + 3) then takes c (2) as the parameter for f(x) to return (0.5x 2^3 - 2 x (2)^2 + 3) then subtracts the two results and divides that answer by dx (0.000001) then prints it rounded to 1dp (the a:.1f part) which gives -2.0

[night wolf]

can anyone help with science?

[vapid spruce]

can someone pls explain this part?

4. Form the pair of linear equations in the following problems and find their solutions (if
   they exist) by any algebraic method :
   V)
   The area of a rectangle gets reduced by 9 square units, if its length is reduced by
   5 units and breadth is increased by 3 units. If we increase the length by 3 units and
   the breadth by 2 units, the area increases by 67 square units. Find the dimensions
   of the rectangle.

original ques for reference

[latent siren]

You just posted the solution??

[left knoll]

@latent siren dude, that was done by someone else .. I need to understand that and need the right explanation 🤦🏻‍♂️

[latent siren]

Man, you need to start taking the effort of asking detailed questions.

I couldn't have known that you need MORE explaining when you just posted the solution yourself. God.

[serene ginkgo]

hey:) @left knoll so pretty much what they're trying to do is simplify (im gonna use alpha = d and beta = e) d^4 + e^4 +(de)^2 into an expression using the terms d+e = -b/a and de = c/a so you can just sub those values in

they start off by finding a way to rewrite d^4 + e^4 so they used (d^2 + e^2)^2 which gives d^4 + e^4 + 2(de)^2

however the question asks for only one (de)^2

which is why they subtract a (de)^2 from (d^2 + e^2)^2

they then simplified d^2+e^2 in a similar way

(d+e)^2 gives d^2+e^2+2de

you only want d^2+e^2 so to get rid of the 2de you subtract it

so the expression d^2+e^2 is equal to (d+e)^2-2de

this now gives you the expression of [(d+e)^2-2de]^2-(de)^2 which is equal to d^4+e^4+(de)^2 (the thing youre trying to find in terms of a,b,c)

at this point they sub in the values d + e = -b/a and de = c/a

then they expanded the brackets and simplified it down

that was so long sorry lol

[left knoll]

Finally! Thank you so much!!

[serene ginkgo]

youre welcome:)

[snow eagle]

can anyone help me

[peak eagle]

give me a second 🙂

[snow eagle]

@peak eagle have you finished

[peak eagle]

it follows with side angle side

paint your the given things in the same color, than you should be able to see it. I could make a foto of a proof but its a german math book...

[snow eagle]

can you

its ok i really need to undertsand this

[peak eagle]

last picture first, and the one with the triangles

[peak eagle]

the proof I just posted is for the Hilbertroom (?) -> don't know if it's the right term in english

[silk quiver]

these are the ways to prove if 2 triangles are conguent

[snow eagle]

thanks @silk quiver and @peak eagle

can you help with this though MAYBE

maybe*

[peak eagle]

start with putting in different numbers for x and then try to think what is in that.
be careful if with the >= and just <

paint those points in the system and afterwards if you still don't know what to do we can see where the problem is 🙂

[snow eagle]

thanks

[silk quiver]

draw the lines first by changing the sign to =

then if y is greater it is the upper part of the graph. if x is greater it is the lower part of the graph. Also if there's an = the line will be straight line and if there's no = then the line to be used is broken lines

[hollow escarp]

Since the question was to do it using any algebraic method. I’ve used a simple method and have tried to explain it within the answer itself. I know the cross multiplication method can look very confusing to you. It’s not very easy to explain via text. So I’d suggest you check a YouTube video of cross multiplication method and learn it. Once you understand that, you’ll be able to follow the solution pretty easily. @vapid spruce

[vapid spruce]

thank you so much@hollow escarp

[vapid spruce]

yes i messed up a - sign in the beginning that's why i was wrong and cross multiplication is somewhat confusing, the website also had a very simplified answer, thank you very much again

[hollow escarp]

No problem.

🤘

[vapid spruce]

😇

[snow eagle]

@silk quiver does this look good

[snow eagle]

so am wrong?

@silk quiver

[silk quiver]

this should not be included

[peak eagle]

only the one with the broken line. there you still to draw (maybe another color) what is on the left/up or right/down side

[silk quiver]

the part where the two colors overlap are the only solutions

[snow eagle]

Thanks

[gentle coral]

Use the information to answer the following question.

Casey conducted research on the amount of time people spent at the mall and the amount of money they spent. Casey calculated the line of best fit as f(x) = 1.05x – 2.63 and correlation coefficient of r = 0.08 for her data set.

Which of the following statements BEST describes the relationship between the amount of money spent and the amount of time people were in the mall?

A.    

The events have a strong positive linear correlation.

B.    

The events have a strong negative linear correlation.

C.    

The events have a weak positive linear correlation.

D.    

There is little or no linear correlation.

what is the answer

[uncut mason]

What do you think the correlation coefficient (r) tells you?

[analog cliff]

hey, can someone help me solve this?

[uncut mason]

here's a hint:

[uncut mason]

hint: multiply both sides of the equation with x(x-6)(x-1)

[pine dust]

Can someone help with this simple indices

The bottom 2..

I can't figure out how to equalise the base

[north temple]

There is another say to do it since you can't easily do thay

Take Ln on both sides

And bring the power outside

[wraith olive]

hey, could someone help me figuring out what the region R is

my head cant deal with modules

[latent siren]

Wolframalpha can really help when you want to graph these kind of things. https://www.wolframalpha.com/input/?i=|x|%2B|y|<%3D1

If you want to do it manually though, you should think about what graphs you'll get by considering four different cases. What does the graph look like if x and y>0, what if x, y <0, what if x>0 while y<0, and finally, what if x<0 while y>0?

Then you look for the intersection of those graphs.

I guess that's how you get the diamond shape.

[north temple]

It's gonna be (sinx)^3/3 +c

[sullen lantern]

use u-sub, u=sinx which gives you du=cosxdx, and from there, integral of u^2 du, then u^3/3+C, then undoing the sub, (sinx)^3/3+C as helloyeah stated

[full badger]

ohh alright thanks bro

[pine dust]

Man

Thank you so much

I appreciate it a lot @silk quiver

here's a heart ❤️

[wide idol]

Does anyone know how to do part b? I have the answer but idk how to do it.

[left knoll]

Am not sure but take Monday and Tuesday or Tuesday and Wednesday probability and add them so it will be like 80%+80% = ... then divided at 2 and that's it

I hope it's right ... Am not sure thou

@wide idol

[wide idol]

yeah i tried that method and i didn't get that answer sadly

[left knoll]

🙁

let me try

[silk quiver]

1st one is 0.8^3

[potent cypress]

2. should be 0.2 * 0.8 * 0.8

but my english is to bad to understand consecutive days

[left knoll]

wait maybe * not plus

[left knoll]

yes yes

but there is one mistake

[silk quiver]

no 2 isn't like that

[left knoll]

i guess

0.8* 0.8 =...

divided into 2

[left knoll]

what about now?☝🏻

the final answer will be 0.32

[left knoll]

idk dude

[left knoll]

try it @wide idol

[wide idol]

okay ill try it thanks.

The final answer is 32/125

thing is i have no clue how they got to that answer

[silk quiver]

the probability for 2 rainis 3C2 * 0.8^2 * 0.2 = 0.384

but we need to subtract the time that it is not consecutive

[wide idol]

the decimal form is 0.256

[silk quiver]

got it

0.384 is for 2 rains no matter what order

there are 3 ways that we can arrange the days in 2, we need to subtract the rain on Monday + Wednesday

therefore 0.384*(2/3)

[wide idol]

im confused, why do you have to times them together?

[silk quiver]

wait i'll write it for you

[wide idol]

sorry im a bit slow aha

[silk quiver]

@wide idol

for the first one it is 0.8^3 because it is 3C3 * 0.8^3 * 0.2^0

[wide idol]

Thank you!!!

[faint thistle]

Really appreciate if someone can answer this

[peak eagle]

for a)
think where the point P would be if it were cos (x)
x-30 means that the roots are shifted

same goes for cosinus: a = stretch/shrink on the y-Axe, b=stretch/shrink on the x-axe, c= shift on the x-axe, d=shift on the y-axe

[peak eagle]

if you need more tips write again 🙂

[left knoll]

can solve this

[north temple]

Have you tried integrating by parts?

[left knoll]

no

i know how to do it but my ans didnt match with the solution

[north temple]

What was your answer?

Like the value

[left knoll]

2-sec0*

[left knoll]

Guys i need help

Where is -(-1) coming from in both of the solutions?

No one's here to help?

[latent coyote]

im not sure but i think they multiplied it to (3b)^2 so that it will be equal to +9b^2

[left knoll]

Okk

[latent siren]

They want to use the identity (z+w)(z-w)=z^2-w^2 for complex numbers

So that -1 is just a tricky way to do it

[left knoll]

damn and i thought my math was hard

you guys have 10X harder math

[left knoll]

YOOOOOOO I got math question pls you geniuses in this chat help me

If I have exponential decay (radioactive element e.g.)
--and I´m asked "decay halfing is every 10h, start is 12800u --> when is 100u reached?

----> WHY am I getting different answers just manually counting down (12800->6400->3200 etc...) FROM using 12800/2^x = 100

I dont understand this, its the same isnt it??

(counting down gives me x = 11 , algebraic solving gives me x = 7

oh no

Im just a retard with an added zero

nvm

[candid rivet]

hope it's not wrong

[tall apex]

anyone here revising for there mock exams????

[silk quiver]

is the answer 70hrs?

[left knoll]

its right thanks man

[topaz narwhal]

any statistics majors in here ?

need help double checking my work

need to convert 2159420.917 to grams. Since after the decimal I have a 9 I simply raise the zero and I would have <<<2159421 >>>

[vestal minnow]

The given function is not continuous througout the limit specified. Hence you cannot apply limit the way that you have.

[hollow pier]

Anyone know how to do 12? I’m not sure what I’m meant to do after anti deriving it

[vestal minnow]

Do you have the answer? Like the final curve equation?

[ruby tinsel]

This is what I got! Let me know if I am wrong 🙂 Btw is that Sadler?!!

[vestal minnow]

I'm getting this

[hollow pier]

yeah thats the answer thank you very much 🙂

[left knoll]

yessir

[atomic elm]

Hi could I have help on both these questions

Thanks 😃

[latent siren]

For (a): This just means that 3x-1 and f(x) share the same root.

So what's the root of 3x-1?

For (b), we know that 3x-1 is one of the factors of f(x), this will give you a hint on how to proceed. Try to factor out the polynomial with that in mind.

[atomic elm]

thx

[latent siren]

If you still don't get it, please ask for more details.

[atomic elm]

yeah

[latent siren]

You know that 3x-1 is a factor of f(x), so you can divide f(x) by 3x-1 by synthetic/long division

[atomic elm]

but the question says use the factor theorum

yeah

how do you do the synthetic dvision bit

[latent siren]

Okay, so let's focus on (a)

The factor theorem says: f(x) has a factor (mx+b) if and only if f(-b/m)=0.

[atomic elm]

yh

ok

[latent siren]

So, in our case, mx+b is 3x+1. What's m and b in this case?

[atomic elm]

3 and 1

[latent siren]

Nice! Now, we are done if we can show that f(-m/b)=0

[atomic elm]

ok

cool

[latent siren]

So just check that f(-1/3)=0

[atomic elm]

you sub in

and if it equals