#help-36

1 messages · Page 213 of 1

gritty flume
#

I don’t get what you mean but thanks

#

so are they always like tht

gritty flume
#

what about the 3rd and forth quadrant

compact saddle
# compact saddle

the theta should be the angle that the curved arrow is showing, not the one under the line

gritty flume
#

and what’s the

#

tae

gritty flume
#

like making a straight line

compact saddle
compact saddle
#

😭

gritty flume
#

oh ok

#

but what about the theta

compact saddle
#

theta is how θ is pronounced

warped perch
#

'The reference angle'

compact saddle
#

yea, positive x axis to be more precise

gritty flume
#

oh ok ok

warped perch
#

But what's the question

gritty flume
#

oh I’m learning the cetesian plane rn

#

actually idk

warped perch
compact saddle
#

the b) question here, tey wanted to know how they should represent it and apparently they needed to use the coordinate system to represent is and not just a trangle

warped perch
#

If Tan and Sin both are +ve it means we're talking about the first quadrant

compact saddle
gritty flume
#

oh ok ok

warped perch
gritty flume
#

i only understand it as the y and x are positive so the first quadrant

#

y is ve and x is negative so second

#

both y and x and negative so third

warped perch
#
  1. Sin^2 x + Cos^2 x = 1
    This will be the line y=x
gritty flume
#

and 4th y is positive and x isn’t

#

i think

gritty flume
warped perch
#

So which grade are you in right now

warped perch
warped perch
gritty flume
warped perch
gritty flume
#

wait kinda of

#

its that the gradient or the equation

warped perch
#

How much do you understand trigonometry?

#

Like do you know that trigonometric ratios?

compact saddle
#

thats not a graph for line

gritty flume
#

ik the formulas

#

how fo ind th enable

#

and side

#

angle

warped perch
gritty flume
#

and side

compact saddle
#

i dont get where you got y=x from

warped perch
#

Yes you're right

compact saddle
#

Sin^2 x + Cos^2 x=1 would even be a graph thechically since you would need x and y

warped perch
#

Idk why I went to tan 🤦🏻

compact saddle
#

anyw skittlx u can ignore what weve been going on abtw

compact saddle
#

a vid would probably help

compact saddle
#

btw were you thought about angles using radians

#

?

warped perch
#

You don't learn that in 10 grade

gritty flume
#

i learn just for learning sake, I don’t learn like the terms or like the topic names with my learning

compact saddle
warped perch
#

You must have learnt that in school

gritty flume
#

is it the sine rule

#

cosine rule?

warped perch
#

Right, so all the 6 ratios let me name them
Sine
Cosine
Tan
Cot
Sec
Cosec
These all are the trigonometric ratios

gritty flume
#

i just found out what the cot, scs and sec meant

warped perch
gritty flume
#

and the triangles without is the other two

gritty flume
warped perch
gritty flume
#

idk when to exactly use the cosine rule tho

#

ill be closing the channel after an hour bc ill learn something else and relearn math

warped perch
#

I see

#

Do you know the names of the three sides of the Right-Angled Triangle

gritty flume
#

unless your referring to the opposite side

#

adjacent and hypetenuns

warped perch
gritty flume
#

oh ok

compact saddle
#

are defined

#

in the coordinate system

gritty flume
#

I don’t think so

compact saddle
gritty flume
#

isn’t it bc the x is negative

compact saddle
#

the way sine and cos are actually defined is by considering a circle of radius r centered at the origin

#

then if you draw a radius making a angle θ with the positive x axis

warped perch
compact saddle
#

sin=y/r
cos=x/r

warped perch
gritty flume
compact saddle
gritty flume
#

i kind of get it in a way

compact saddle
#

😭

compact saddle
warped perch
#

You understand degrees right?

gritty flume
#

yeah

warped perch
gritty flume
#

oh ok ok

compact saddle
# gritty flume what are radians

they way i would explain it: basically, its a way we define angles so that we can use pure real numbers instead of degrees

we consider a unit circle, if a given arc of a=the unit circle(radius=1) subtends a angle of θ at the centre, we say the angle is (arc length) radians, so 360 degrees (the arc is the entire circumference)=2pi radians

https://www.youtube.com/watch?v=e7QjCL7lQM4&t=1091s, you can look at the "why radians" part of this vid

also you can look up about radians on chrome or yt for more vids

Get better at trig and so much more math at https://brilliant.org/TreforBazett to get started for free for 30 days, and to get 20% off an annual premium subscription!

This video is all about trigonometry, focusing on reviewing everything you are likely to actually use regularly in calculus. Instead of having to memorize a million trig identitie...

▶ Play video
#

ignore the later half of the vid, you dont really need those formulas rn

gritty flume
#

dang the close up

#

looks like he would slap me

compact saddle
warped perch
#

Are you familiar with the topic

warped perch
warped perch
compact saddle
#

LOL

#

we can crack our heads togeather in dms if u want

warped perch
#

Lol you in the same boat you mean?

compact saddle
#

but the chap isnt finished yet

warped perch
#

I haven't really started with it tbh, but I know the 10th part well

compact saddle
compact saddle
#

so i may be able to help depending on what ur stuck on

#

idk

warped perch
#

Where u from

compact saddle
#

we can move to dms if u wanna talk

compact saddle
#

or not no pressure

warped perch
#

Sure idm

compact saddle
compact saddle
#

sry about us lmao

gritty flume
#

like later

#

nah Idm

#

this server is to help

#

so it’s all good

compact saddle
#

whichever you feel more comfortable with

gritty flume
#

unlesss the channel gets taken by another person then ill dm

compact saddle
#

sounds good

#

!!

#

idk much about how the help channels here work im not 100% sure if your alowed to just keep it up

#

i think it closes itself after a period of inactivity

#

you can reopen one later and ping me if that happens

final saddleBOT
#

@gritty flume Has your question been resolved?

#
Channel closed

Closed by @gritty flume

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

chrome hemlock
final saddleBOT
chrome hemlock
#

how do I find the angle of z2

#

to put in rcis(theta) form

tired walrus
#

you read it off from the diagram

#

conveniently, said diagram has a polar grid

severe canyon
#

The rays are how far apart? How many degrees? Can you recognise that?

chrome hemlock
#

is it 5pi/12

#

is it red or blue

tired walrus
#

wym red or blue

chrome hemlock
tired walrus
#

does your class take arguments from 0 to 2pi or from -pi to pi

severe canyon
chrome hemlock
#

this is how they calculated iz2

severe canyon
chrome hemlock
#

oh wait it tells me an easier way

severe canyon
tired walrus
#

do you have any class materials from when you were introduced to argument

chrome hemlock
#

lemme check my one noter

#

is this principal?>

tired walrus
#

good

#

that means arg(z_2) is indeed -5pi/12

chrome hemlock
#

ok thanks

final saddleBOT
#

@chrome hemlock Has your question been resolved?

#
Channel closed

Closed by @chrome hemlock

Use .reopen if this was a mistake.

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

hollow needle
#

its obviously just yes right?

final saddleBOT
hollow needle
hasty mist
hollow needle
hasty mist
#

Intuitively?

hasty mist
# hollow needle im having a hard time understand why it must be trhe

When you intersect more sets, you get something smaller or equal because you’re imposing more conditions for membership. Since I includes all of J, the intersection over I includes more sets in the intersection, so it can only get smaller or equal to the intersection over J

versed crater
#

Pick something from the left

#

Then it is in every A_I

#

If you then pick a subset of these I’s all of them should (and does) still have the something

hollow needle
#

.close

final saddleBOT
#
Channel closed

Closed by @hollow needle

Use .reopen if this was a mistake.

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

worthy radish
#

With quadric equations, I’m finding “x” using the delta solutions because the whole equation isn’t solvable otherwise using the regular algebra rules?

compact saddle
worthy radish
#

For example here what method would you guys use here?

compact saddle
#

but somewhere along the derrivation you end up assuming b^2-4ac isnt negative if x is a real number

#

however, when we consider complex numbers, the quadratic formula can give you the answer for any equasion, just that the equations where b^2-4ac is negative have complex solutions

compact saddle
#

the derrivation of the quadratic quasion uses a method called "completing the square" which can also be done on any quadratic

#

since the square root function is only defined when the thing inside it is positive, then you can see how the derrivation assumes (b^2-4ac)/4a^2 is positive, but since 4a^2 is always positive, we only need b^2-4c to be positive

#

for square roots to be defined for negative values, you need the coples numbers

worthy radish
#

Because I don’t have “c”

#

Here once again I need to use another method of solving cause i don’t have “b”….

#

So there are 3 ways of solving quadric equations

compact saddle
worthy radish
#

I can’t use bracket method if abc

#

@compact saddle

compact saddle
#

remember a^2+b^2+2ab=(a+b)^2?

worthy radish
#

But what’s the ultimate goal for quadric equations? To know what the x is that leads to 0?

compact saddle
#

so yes, it is to find out what x implies ax^2+bx+c equates to 0

compact saddle
#

its actually quite useful to know

#

allows you to express the quadratic in a more useful way in some contexts

#

(like solving integrals for example, but you dont have to worry about that for now)

worthy radish
#

But why can’t we solve x?

compact saddle
#

wdym?

#

can you elaborate

worthy radish
#

Why can’t we move 1 to 0

#

So it’s -1

#

And then divide by -4

compact saddle
#

yes

#

you can still solve for x

worthy radish
#

How

compact saddle
#

you have to use, a^2+b^2+2ab=(a+b)^2

to bring your equasion in the from of kx^2+n=0

compact saddle
#

clue is that you try to add and subtract a number

#

its the same this as adding a 0

#

or just tell me u just want the method

final saddleBOT
#

@worthy radish Has your question been resolved?

final saddleBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

dense garnet
#

Let $(Y_n)$ be a sequence of i.i.d. real random variables with a symmetric distribution (i.e. $Y_n$ has the same law as $-Y_n$). Assume that $\frac1{n}(Y_1+\cdots+Y_n)$ has the same distribution as $Y_1$, for every $n$. Show that $Y_n$ follows a Cauchy distribution.\

Using properties of characteristic functions (cf), where $\phi$ is the cf of $Y_i$, I arrive at the functional equation $$[\phi(t/n)]^n = \phi(t)\quad\forall t\in\mathbb{R}$$Clearly $e^{|t|}$ satisfies this, which is the cf of the standard Cauchy distribution. But is it the only one? (Also, $\phi$ is a real-valued function.)

soft zealotBOT
final saddleBOT
#

@dense garnet Has your question been resolved?

final saddleBOT
#

@dense garnet Has your question been resolved?

final saddleBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

sturdy badge
#

need help with this

final saddleBOT
sturdy badge
#

work so far

atomic moon
#

Why e on top?

sturdy badge
#

would e not be a

atomic moon
#

When its sum a*r^n

#

Here you have e^cn which is (e^c)^n

#

"a" would be 1

#

in fact a is the first term of the sum which is 1 here

echo carbon
#

hi

sturdy badge
#

o h h h h

atomic moon
#

Except this it should work

final saddleBOT
#

@sturdy badge Has your question been resolved?

#
Channel closed

Closed by @sturdy badge

Use .reopen if this was a mistake.

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

polar spruce
#

<@&268886789983436800> castrate this guy

final saddleBOT
#
Channel closed

Channel closed due to the original message being deleted.
If you did not intend to do this, please open a new help channel,
as this action is irreversible, and this channel may abruptly lock.

polar spruce
#

thank you

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

peak owl
#

hi im stuck where do i start with this

final saddleBOT
gray vortex
peak owl
#

im just stuck on the approach

#

i feel like its smth to do with a triangle

gray vortex
#

what have you done so far

severe verge
#

you want the shortest distance from P to (4,0)

#

do you know distance formula?

peak owl
#

no

#

i do not actually

#

didnt know it existsed

gray vortex
#

do you know pythagorean theorem

peak owl
#

yes

#

ofc

gray vortex
#

well it's the same

peak owl
gray vortex
#

yes

peak owl
#

ok

#

thanks

#

.close

final saddleBOT
#
Channel closed

Closed by @peak owl

Use .reopen if this was a mistake.

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

twin wing
#

can you check if i math this correctly

final saddleBOT
#

@twin wing Has your question been resolved?

hasty mist
twin wing
#

lol thats what im saying

#

something is wrong with my math here

final saddleBOT
#

@twin wing Has your question been resolved?

serene panther
#

From what I know of physics, Intensity is inversely proportional to square of distance between point source to that point

#

In this case

#

But youve taken it to be directly proportional

#

@twin wing

deft terrace
#

I=P/A

#

the power is same here

#

so IA = constant

#

or Ir^2 = constant

final saddleBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

drowsy juniper
#

I'm trying to understand a Pythagorean Triangle problem using the Speed of Light in one second (299792458m) as leg A, and the Plank Length (1.61 * 10^-35m) as leg B. Every time I calculate it in C++ using boost there's no difference in the hypotenuse and leg A. Does the triangle break at one point at certain lengths?

mint orbit
#

you're hitting the limits of precision though

#

how much comp sci do you know

drowsy juniper
#

Not much, just getting started in community college.

mint orbit
#

to answer your question directly, math on a computer with very small and very big numbers is usually error-prone

#

you might look into how a computer stores numbers

#

idk what types youre using here

drowsy juniper
#

Okay, I'll try something else. Also taking the inverse cosines of the angles posits one angle to be 90 degrees in at the end of the B side. I think I found something but just want to actually test it.

#

So it becomes a 90, 90, really small degree angle.

mint orbit
#

youre bumping against a common problem in computing so its probably worth exploring if youre curious

drowsy juniper
#

Okay, thanks man. Just seeing if I was losing my mind about the triangle always holding.

#

.close

final saddleBOT
#
Channel closed

Closed by @drowsy juniper

Use .reopen if this was a mistake.

mint orbit
#

sure, no problem catthumbsup

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

twin wing
final saddleBOT
#

@twin wing Has your question been resolved?

final saddleBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

rotund parrot
#

for part b, how am i supposed to find the two vectors that i need to find the angle between?

rotund parrot
#

this is what the asnwers say

#

i dont know how they got there

odd seal
#

the only time dependent component gives you the velocity here (v = dr/dt)

#

and that has a vector direction of [40, -100, 0]

#

and while descending, you know the z component is additionally -16km/h, so the new vector becomes
original velocity + [0, 0, -16]

final saddleBOT
#

@rotund parrot Has your question been resolved?

final saddleBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

fair sigil
#

midpoint of OH , right

final saddleBOT
severe verge
#

correct

fair sigil
#

thanks

#

and sorry for late

severe verge
#

only takes 3 days to respond sadly

fair sigil
#

sorry

#

bye

#

thanks

#

.close

final saddleBOT
#
Channel closed

Closed by @fair sigil

Use .reopen if this was a mistake.

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

severe robin
#

trying to solve using mathematical induction. I know this isn't the way to do it however I think I'm still proving it (?). I'm asking for help on how to properly use inductions to prove this

thorny canyon
#

assume it holds for n=k

#

use that to prove that it must hold for n=k+1

#

$6^{n+1}-1 = 6^{n+1}-6+5=6[6^n-1]+5$

soft zealotBOT
#

Donkey

severe robin
thorny canyon
#

factor out 6 from 6^{n+1}-6, leave 5 untouched

severe robin
thorny canyon
severe robin
#

not sure how to use the image bot

thorny canyon
#

dollars front and back

#

but yeah, you're right

severe robin
#

ohh

#

$6^{k}-1=5t$

soft zealotBOT
thorny canyon
# severe robin

so you js substitute that in the last part of this expression

#

$6[6^k-1]+5 = 6(5t)+5$

soft zealotBOT
#

Donkey

thorny canyon
#

and that's done

severe robin
thorny canyon
#

the core idea of induction is that you prove a base case, make an assumption abt it holding for some random integer k, and prove that if it holds for k, it must hold for k+1

#

so the thing where we substituted $6^k-1=5t$ is us implementing the "if it holds for k" condition

soft zealotBOT
#

Donkey

thorny canyon
#

the remaining part is js taking 5 common, so $6(5t)+5=5(6t+1)$ which is clearly divisible by 5

soft zealotBOT
#

Donkey

severe robin
soft zealotBOT
severe robin
thorny canyon
#

np

severe robin
thorny canyon
#

I'm a hs senior

#

js enjoy math

severe robin
thorny canyon
#

thanks

final saddleBOT
#

@severe robin Has your question been resolved?

#
Channel closed

Closed by @severe robin

Use .reopen if this was a mistake.

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

mystic patio
#

In EDA should you do analysis first and then clean the data or the other way around

final saddleBOT
#

@mystic patio Has your question been resolved?

final saddleBOT
#

@mystic patio Has your question been resolved?

final saddleBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

bronze grove
#

hola

final saddleBOT
bronze grove
#

ik its easy but i dont know how to do it

abstract bramble
#

maybe you should start by finding the solutions to those inequalities

bronze grove
true escarp
bronze grove
true escarp
#

okay

#

so just transform the middle part of that expression to |x - 4|

#

what do you think the first step is?

bronze grove
#

im ug maths 😭

#

u dont need to be that specific

bronze grove
#

i need to understand in this form

steep hatch
# bronze grove

A general tip I'd suggest for something like this is try to find an equality relating |x-4| to |\sqrt{x}-2|

bronze grove
steep hatch
#

I mean okay, first can you find the equality I hinted at

bronze grove
#

yes wair

bronze grove
#

i think i should read the chapter once

steep hatch
#

okay so that's not what I was thinking

#

what I'm thinking is

#

[ |x-4|= |\sqrt{x}+2| |\sqrt{x}-2|]

soft zealotBOT
#

lance lance

steep hatch
#

So like do you know geometrically @bronze grove what |x-4| represents?

steep hatch
#

what is it?

bronze grove
#

a line?

#

V shape i think

steep hatch
#

no like not as a shape

#

what is the geometric interpretation of the number |x-4|

#

if I fix a value of x

bronze grove
#

like on a graph?

steep hatch
#

no

bronze grove
steep hatch
#

Like the number |x-4|

#

we're not doing graphs

bronze grove
#

yes

steep hatch
#

if I tell you a value of x

bronze grove
#

like if x is 1

steep hatch
#

what does |x-4| mean

bronze grove
#

then its 3

steep hatch
#

Okay and what does that 3 mean

bronze grove
steep hatch
#

the point is that |x-4| is the distance between x and 4 right

bronze grove
steep hatch
#

So if I tell you |x-4|<1, that means the distance between x and 4 is at most 1

#

so what values can x be then?

bronze grove
#

3 and 5

steep hatch
#

well between 3 and 5

steep hatch
#

you then know that sqrt{x} is between what two numbers?

bronze grove
#

yeppp

#

wait i did it the other way

bronze grove
#

by assuming lambda < 1

steep hatch
#

And basically the game we play here is we go

bronze grove
steep hatch
#

\begin{align*}
|\sqrt{x}-2| &<\varepsilon \
\implies |\sqrt{x}-2| \cdot |\sqrt{x}+2| &< \varepsilon \cdot |\sqrt{x}+2| \
\implies |x-4| &< \varepsilon |\sqrt{x}+2|
\end{align*}

#

and what you need to convince yourself of is

#

we can go backwards

soft zealotBOT
#

lance lance

bronze grove
#

it will be plus on other side?

#

yes ok

#

OH

steep hatch
#

So if we start off by already saying |x-4| < 1, then we know that |\sqrt{x}+2|< \sqrt{5}+2, which we'll round to 5

#

So we can then say that

#

our condition will be $ |x-4| < \mathrm{min}( 5\varepsilon, 1)$

#

huh

#

anyway

bronze grove
#

our condition will be $|x-4| < \mathrm{min}( 5\varepsilon, 1)$

soft zealotBOT
steep hatch
#

convince yourself now that using this we can go backwards to get |\sqrt{x}-2|<\varepsilon

bronze grove
#

wait here did the 5e come from

#

thats the part i was confused in

steep hatch
soft zealotBOT
#

lance lance

bronze grove
#

OHHH

#

OK

#

I GET IT

#

THANK UUUU

steep hatch
#

No worries :)

bronze grove
#

tysmm

#

.close

final saddleBOT
#
Channel closed

Closed by @bronze grove

Use .reopen if this was a mistake.

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

final saddleBOT
#
Channel closed

Channel closed due to the original message being deleted.
If you did not intend to do this, please open a new help channel,
as this action is irreversible, and this channel may abruptly lock.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

fierce timber
#

Hi im a 9th grader can someone help me explain how do i get the 8 in front of the (y-2) photomath gives me that buti dont understand tbst step

craggy plank
#

,rccw

soft zealotBOT
magic meteor
#

Got that math teachwr handwriting already, keep it up.

#

Think of it this way, what did we factor out of the first parenthesis

pliant shore
#

$2y - 4 = 2(y - 2)$ and $4y^2 + 8y + 16 = 4(y^2 + 2y + 4)$

soft zealotBOT
fierce timber
smoky bramble
magic meteor
fierce timber
#

oh so basically i divide the first one by 2 and the second one by 4 and thats like multiplying both by 8?

magic meteor
#

Walk be through your steps

fierce timber
magic meteor
#

We removed 2 from the first parenthesis right?

#

And 4 from the second

fierce timber
#

and so basically thats like multiplying everything by 8?

magic meteor
#

Yes, we factor out 2 and 4, and since the parentheses are being multiplied we just multiply the factors and we get 8

fierce timber
#

it all makes sense now, thanks

magic meteor
#

Np

fierce timber
#

because my actual notebook is way worse

#

everything is so messy

magic meteor
#

Uhh, dont even worry about it, my physics homework is terrible

pliant shore
#

I can clearly tell that's y and not g

magic meteor
#

This is unironically how mine is

vestal crest
#

the only nitpick I can see about the handwriting is the possibility of misreading the 4 for an a, but that should be highly unlikely.

magic meteor
#

Terrible

fierce timber
#

i gave a really god example there

#

with the picture

vestal crest
pliant shore
magic meteor
magic meteor
pliant shore
#

it is readable but it's just annoying to read

fierce timber
#

does someone understand 18.b we wrote a pop quiz that wasnt for grade and i got 0/10 from this part

pliant shore
#

because $2^2 (ab + 1)^2 = [2(ab + 1)]^2$

soft zealotBOT
magic meteor
fierce timber
#

in the exercise the solution should be (2a-1)(2a+1)(b-2)(b+2)

#

how do i get that

pliant shore
fierce timber
#

and it has quite a few steps i believe

fierce timber
magic meteor
#

Smart≠good at math

pliant shore
#

or you could write $x^2 - y^2$ first and factor that

fierce timber
#

im sorry i dont understand the question

soft zealotBOT
pliant shore
#

so you keep factorising until there's nothing left to factorise

fierce timber
#

the exercise is to factor it

#

and i dont know how to do it

pliant shore
fierce timber
#

x-y) (x+y

#

im lazy to write

#

whole parenthesis

pliant shore
#

right! so the idea is with $[2(ab + 1)]^2 - (4a + b)^2$

soft zealotBOT
pliant shore
#

we use $x = 2(ab + 1)$ and $y = 4a + b$

soft zealotBOT
pliant shore
#

sub those in

fierce timber
#

wait i dont understand what text should i look at

magic meteor
#

Its a bit unintuitive to go straight to factors when youre new to it. I reckon we should expand the squares

pliant shore
fierce timber
magic meteor
#

8ab

fierce timber
#

like doesnt it square the whole thing?

pliant shore
#

because what you're doing is trying to expand that

magic meteor
#

Expand the squares, sum them, factor

pliant shore
fierce timber
#

i think i should learn english math terminology so i can understand what yall saying

pliant shore
#

this is absolutely a difference of 2 squares exercise

magic meteor
fierce timber
#

oh wait i think i understand, im supposed to make it have 2 parts so i can do the x-y) (x+y

leaden moon
#

coolio

#

yes

pliant shore
#

I bet they haven't learned how to factorise 4uv - 16u - v - 4 as (2u + ...)(2v - ..) or (4u + ...)(v - ..)

pliant shore
#

you want to get the multiplication of some brackets

#

because the parts in each bracket are simpler

fierce timber
#

but like dont give the answer immediately i mean its fine if you do

fierce timber
pliant shore
fierce timber
#

imma try

magic meteor
#

A^2-B^2=(A-B)(A+B)

pliant shore
fierce timber
#

i tried and got it so wrong

#

i got

#

(x-y) squared

magic meteor
#

You remember the double negative rules?

pliant shore
#

your factorisation should be using a and b

fierce timber
magic meteor
fierce timber
#

oh yeah that

#

yeah i know

pliant shore
#

but it helps to be aware of similar rules

magic meteor
#

Odd number of lines and its negative, even number and its positiveopencry

fierce timber
#

i get to the step the first one where i have (x-y) squared (x+y) squared - (x+y) squared

magic meteor
#

Is this 18.3?

fierce timber
#

yeah

pliant shore
#

by 'sub', I mean find x, and replace it with 2(ab + 1)

#

every time you see x, replace it with 2(ab + 1)

pliant shore
fierce timber
#

wait what

#

wdym

magic meteor
#

Just different numbers

fierce timber
#

how do yall se that as the same thing

magic meteor
#

Same method

#

Numbers dont matter in mathsopencry

pliant shore
#

you use (x + y)(x - y) for all of them

fierce timber
#

im still trying to figure out

#

everytime i get different answer

pliant shore
#

what are you getting now?

fierce timber
#

imma send pic rq

#

here you can see both the answers i got

pliant shore
#

it's $[2(ab + 1) + (4a + b)][2(ab + 1) - (4a + b)]$

soft zealotBOT
pliant shore
#

again, you should use brackets surrounding the y first (cause you need to subtract it)

#

then you can drop them later

magic meteor
#

Important to define what x and y is in this context

pliant shore
#

x = 2(ab + 1) and y = 4a + b to remind you

#

yeah, I see you're getting the idea for 18.3 too, but you're further off

fierce timber
#

imma try doing it again with the info you just gave me

#

to see if i get any closer or actually solve it

pliant shore
#

do not try and expand x^2 - y^2 or factor it just yet

magic meteor
#

We substitute first, then expand

pliant shore
#

it's substitute first then factor

fierce timber
#

i got it right but i pretty much guessed

#

like i didnt get it right because i completely understood it

magic meteor
#

Ok so think of it this way. We have two squares right?

#

We call one x and the other y.

#

If we want to find the difference between them, we have to do x^2 - y^2=(x+y)*(x-y)

#

First of all, lets do 18.3. What is x and y in that context?

fierce timber
#

youre asking me to compare it to 18.2?

magic meteor
#

No lets solve it from the bottom

#

What is x and y in 18.3

pliant shore
# fierce timber

do you see how you can get $(x^2 - y^2 + x + y)(x^2 - y^2 - x - y)$?

soft zealotBOT
fierce timber
#

what should i answer first

magic meteor
#

What is x and y first of all

#

Thats the fundamentals

#

In 18.3

fierce timber
#

actually without the squared at the end

magic meteor
#

Last page of your special symbols there should be ^

#

we use that to denote squared

#

So x^2

fierce timber
#

how to type it

magic meteor
#

Phone or pc?

fierce timber
#

pc

magic meteor
#

Look carefully on your keyboard for the upwards arrow, it varies with region

#

For me its next to enter

fierce timber
#

how is the szmbol called so i can google it

pliant shore
#

try 'caret'

fierce timber
#

no wait actually i have better solution

#

alr so is this correct
in 18.3
x- (x^2-y^2)
y- -(x+y)

pliant shore
#

no minus sign

fierce timber
#

oh yeah mb

pliant shore
#

otherwise that's correct

magic meteor
#

I hate how the names for the squares are the same as the factors

#

Just stick with a and b😭

pliant shore
#

yeah it's an abuse of notation to say that

fierce timber
#

so should i try to replace x with a and y with b and solve it like that

pliant shore
#

you'd need to say X = x^2 - y^2 and Y = x + y

fierce timber
#

like we switch

#

alr let me rewrite

#

alr i replace

magic meteor
#

Write the equation now

fierce timber
#

i wrote

#

[(a^2-b^2)+ (a+b)] [(a^2-b^2)-(a+b)]

magic meteor
#

Yup,

fierce timber
#

so im on the right track?

magic meteor
#

Now simplify

#

Lets do the first bracket

pliant shore
#

now you can expand the brackets, yes

fierce timber
#

wdym by expand

#

does that mean that you want the first part of the first bracket (a^2-b^2) to make it (a-b) (a+b)

pliant shore
#

so (a - b)(a + b) + (a + b)

fierce timber
#

and i do that for both parts or just the first

pliant shore
magic meteor
#

We do the first first and the second secondopencry

pliant shore
#

you need to factor both brackets

fierce timber
#

like this?

magic meteor
#

We should prolly collect like terms to avoid confusion before expanding tbh

fierce timber
#

yeah cuz from 1st to 8th grade everything was in italian and now 9th grade everything is in croatian so my terminology that i know is like split in half with italian and croatian and i know a bit of it in english

magic meteor
#

Math is math, the symbols may change but the methods stay the same

#

We usually do everything in the english alphabet, since its more international

fierce timber
#

wait so am i on the right track if you look at the last thing i wrote

pliant shore
fierce timber
#

and how do i do that

pliant shore
#

(a + b)(a - b) + (a + b)(1), that's the same as the first, do you agree?

fierce timber
#

wait what

#

yeah thats the same

#

cuz anything multiplied by 1 is 1

#

i mean

#

that

#

by 1

#

is that

#

like x by 1 is x

magic meteor
#

Correct

fierce timber
#

my bad my fingers are faster than my brain

pliant shore
fierce timber
#

wait i think i see what you mean

magic meteor
#

Ok, lets start with the first bracket step by step, [(a^2-b^2)+(a+b)]=[a^2-b^2+a+b] right?

fierce timber
#

yes

magic meteor
#

If we wanted to collect all the as together and the bs together how would we do that

#

With parenthesis

fierce timber
#

wait but then my last step was useless?

pliant shore
#

keep going

fierce timber
#

yeah but my step and the one he showed me go in diffeent directions

#

i feel like his is more simple

magic meteor
#

Theyre both right

fierce timber
#

imma go with yours

magic meteor
#

I just prefer to collect like terms before expanding

#

What do we do next then?

#

If we want to collect as together and bs separate?

fierce timber
#

if i do that i get (a^2-b^2+a+b) (a^2-b^2-a-b)

magic meteor
#

???

#

Wait yes

fierce timber
magic meteor
#

But we want to keep them in brackets for now

magic meteor
#

Dont dissolve the parenthesis

fierce timber
#

but thats what you did here

magic meteor
#

Yes, correct, its just better to do them separate😭

#

Since it avoids confusion

#

Lets start with grouping terms, (a^2-b^2+a+b) =[(a^2+a)-(b^2-b)] right?

fierce timber
#

yes

magic meteor
#

So now we have two parts. What can we do?

pliant shore
fierce timber
#

i can send u the way my teacher did it its way shorter but like way more complex

magic meteor
fierce timber
pliant shore
#

a(a + 1) - b(b - 1) is not a valid factorisation

magic meteor
pliant shore
#

fair

magic meteor
fierce timber
#

this is how he did it

pliant shore
#

oh that'sneat

#

hopefully you understand it

magic meteor
#

Wait are we going for a linear system or a factored system??

fierce timber
#

i have no idea waht you just said

#

the exercise says

#

rastavi na faktore which means decompose into factors

magic meteor
#

Classic vague maths

fierce timber
fierce timber
pliant shore
#

cause $(a - b)^2 - (1)^2$ is another difference of squares

soft zealotBOT
pliant shore
#

oh wait before that

magic meteor
#

Should be -(1^2) tbh

pliant shore
#

if you divide $(a - b)^2 (a + b)^2$ by $(a +b)^2$, you get $(a - b)^2$

soft zealotBOT
pliant shore
#

now if you divide $(a + b)^2$ by $(a + b)^2$...

soft zealotBOT
fierce timber
#

thats just 1?

magic meteor
#

@pliant shore Are we going for [a(a - 1) - b(b + 1)] * [a(a + 1) - b(b - 1)] or the linear form😭

#

Theyre both fully factored technically

pliant shore
#

cause that's not a product of brackets

pliant shore
magic meteor
#

Alr fair, only linear factorscatthumbsup

fierce timber
#

i kinda understand now

magic meteor
#

I mean what your professor wrote is the solution 🙂

fierce timber
#

basically we got that for homework 2 weeks ago and someone asked if he could explain it which he didnt do he just solved the exercise without explaining

magic meteor
#

I do think that it should be -(1^2) rather than -1^2 but i guess its just semantics

magic meteor
#

Its hard to explain

fierce timber
#

and even harder to understand

magic meteor
#

Pretty much, if it helps, consider factors to be a polynomial just divided up, whenever you have a group of factors you can go backwards and create a polynomial.

#

@pliant shore Gotta go, freezing my hands off writing this so imma go inside

fierce timber
#

yall so nice ty guys

pliant shore
#

if you're done, type .close

fierce timber
#

.close

final saddleBOT
#
Channel closed

Closed by @fierce timber

Use .reopen if this was a mistake.

final saddleBOT
#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

plain rain
#

if a sequence diverges does that mean that every subsequence of it also diverges?

half raptor
#

no

#

👍

lethal totem
#

Think!

tired walrus
plain rain
#

oh yeah true

#

maybe wed have to mention its monotonous too

lethal totem
#

(-1)^n

plain rain
#

anyways thanks

#

.solved

final saddleBOT
#
Channel closed

Closed by @plain rain

Use .reopen if this was a mistake.

rocky tusk
plain rain
#

.reopen

final saddleBOT
rocky tusk
#

(-1)^n doesn't diverge?

#

what does (-1)^n converge to

plain rain
#

doesnt

rocky tusk
#

brother

#

diverges means doesn't converge

#

diverges doesn't mean diverges to infinity

bleak granite
#

it's bounded but not convergent

plain rain
#

yeah but also not divergent

rocky tusk
#

dawg

plain rain
#

look

bleak granite
#

we define divergent by not convergent

plain rain
#

| a_n | < 2

bleak granite
#

yes

plain rain
bleak granite
#

it's bounded

rocky tusk
#

this is a definition

plain rain
#

but divergence means a_n > M for every positive M in R. or -M

rocky tusk
#

no it doesn't

plain rain
#

huhhhh

bleak granite
#

that's just the opposite of bounded

rocky tusk
#

thats unbounded

plain rain
#

oh i see

bleak granite
#

a sequence being bounded is not a sufficient condition of it converging

plain rain
#

im not talking abt convergence

rocky tusk
#

there is no such thing as a sequence neither converging or diverging

#

divergence is the literal negation of convergence

plain rain
#

divergence. i thought if it doesnt converge to a point, but also doesnt diverge to infty, it doesnt diverge

rocky tusk
#

no

plain rain
#

okeoke

#

i got confused

rocky tusk
#

there are many ways a sequence can diverge

#

diverging to infinity is just one of them

plain rain
#

got it

#

thanks

#

.solved

final saddleBOT
#
Channel closed

Closed by @plain rain

Use .reopen if this was a mistake.

formal trail
#

if it doesn't converge to a point, then it diverges, full stop

lethal totem
plain rain
#

nono i was just asking

lethal totem
#

That's actually an interesting question though

plain rain
#

.reopen

final saddleBOT
plain rain
#

ann previously showed us such a sequence

#

but its not ascending like >, but like >=

lethal totem
#

Yeah that makes sense

plain rain
#

.close

final saddleBOT
#
Channel closed

Closed by @plain rain

Use .reopen if this was a mistake.

#
Available help channel!

Send your question here to claim the channel.

Remember:
Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
Do not immediately ping people or roles. After 15 minutes, feel free to ping <@&286206848099549185> once.
• Type the command .close to free the channel when you're done.
• Be polite and have a nice day!

Read #❓how-to-get-help for further information on how to ask a good question, and about conduct in the question channels.

gritty flume
#

Can I get help w question 3

final saddleBOT
tired walrus
#

ok, that's definitely a lot of threes running around

#

how far did you get on your own thus far

gritty flume
#

I got my answer wrong

#

The vid I watched said you multiply the 3s below

tired walrus
#

show your attempt and we can diagnose it

gritty flume
#

I don’t understand why

tired walrus
#

show your attempt so that we can see where and how you went wrong

gritty flume
tired walrus
#

ok i see two mistakes

#

the second of which is that 3x^(3+3+3) somehow had its x completely evaporate into nothing

#

actually no i see more mistakes

gritty flume
#

I multiplied

tired walrus
#

on the bottom, you have:

3 * x^3 * 3 * x^3 * 3 * x^3

#

there are three 3's in the product

#

those become 27, not just a single 3

gritty flume
#

Wht tho

#

Why

tired walrus
#

why what

gritty flume
tired walrus
#

remember that when a number and a letter stand next to each other in algebra, it means multiplication

#

$3x^3$ is really $3 \cdot x^3$, agree or disagree?

gritty flume
#

Yes

soft zealotBOT
gritty flume
#

Yes

#

I agree

tired walrus
#

on the bottom, you have:

3 * x^3 * 3 * x^3 * 3 * x^3

#

or

3 * 3 * 3 * x^3 * x^3 * x^3

#

do you understand now what went on in the denominator

gritty flume
#

I still don’t get it

tired walrus
#

ok lets try to forget about that for a bit

#

here is a different expression

#

i want you to simplify this for me:

#

2a * 4a

gritty flume
#

Idk how to do it

tired walrus
#

again,

#

when two things are next to each other,

#

it means multiplication,

#

so 2a * 4a breaks down into 2 * a * 4 * a

#

understand?

gritty flume
#

Yes

tired walrus
#

multiplication is commutative,

#

so these factors can be written in any order you like,

#

for example as 2 * 4 * a * a

#

understand?

gritty flume
#

Yes

#

Kind of

tired walrus
#

there's no kinda, you either understand what im talking about or you dont

gritty flume
#

Does it become 8a^2?

tired walrus
#

yes 8a^2 is correct

gritty flume
#

Ic

tired walrus
#

now can you do the same thing to 3x^3 * 3x^3 * 3x^3

gritty flume
#

Like this?

tired walrus
#

x^3

#

don't miscopy the 3 exponents as 2's

#

you did that all three times kekehands

#

also your fraction bar is way way too short and those x's are very sad in the rain

gritty flume
#

I’m sorry

tired walrus
#

correct other than this

#

go fix those errors

#

the fraction bar and the miscopies

gritty flume
tired walrus
#

ok

#

and can you simplify on the bottom now

gritty flume
#

I don’t know how to do the x

#

Ohh

#

So the 3 multiply

#

And the card

#

Add

#

X

#

Tysm

#

I still need help

tired walrus
#

ok, so what did you get in the denominator then

gritty flume
#

I got 27x^9

#

Can you tell me the rules for this

#

Bc it’s way different form what Ik

tired walrus
#

the rules for... what exactly

gritty flume
#

The question you helped me w

#

What Ik is same base and it’s multiplying means you add

tired walrus
#

i dont really know what "rules" i could possibly give you

tired walrus
#

but phrased in a wonky way

gritty flume
#

I don’t get it

tired walrus
#

i am taking the thing you're saying and rephrasing it with more proper wording.

#

im struggling to think of any rules that i could give you to memorize as mantras

#

cause like, idk

#

when a number and a letter stand next to each other in algebra, it means multiplication

#

thats the closest i can give you

#

you maybe need to go back to easier questions to repractice

gritty flume
#

I don’t have time

#

I have an exam tomorrow

#

And other thing to study

#

What about question 4

#

The guy in the video did 4.4^x as the denominator

tired walrus
#

when you add four of the same thing together, it is the same as multiplying that thing by 4

granite ivy
#

Yes

tired walrus
#

$a+a+a+a=4a$

soft zealotBOT
tired walrus
#

no deep magic or mystery or arcane rule here

gritty flume
#

I get it

#

But what does the 4 multiply