#help-0

1 messages · Page 553 of 1

cyan token
#

8?

thorny iris
#

Basically you need to make a 5 letter word

#

You have 5 slots

#

There are no repeating letters

#

So in the first slot you have 8 possible letters

#

After you use that letter you now only have 7

#

After you use one letter there you only have 6

#

And it goes on till 5 letters are used

#

8x7x6x5x4

#

Because no repeating is allowed

#

You only have 3 letters left which you can’t make a word with

#

Because it’s a 5 Letter word

cyan token
#

except if its 8! then isnt that combinations, not words

#

they need to be real words not just random combos

thorny iris
#

Combinations is when order does not matter

#

In this case you have to arrange the words a certain way

#

So it’s permutations

#

It’s not like explicitly finding the amount of words

#

Is this a textbook problem? Like do you have the answer to it?

cyan token
#

the question: From the letters in the word "Numeracy" how many 5 letter 'word' arrangements can be made?

#

yes I do, but I don't want to look at the answer key just yet

thorny iris
#

Yeah the answer should be 8x7x6x5x4

#

They shouldn’t expect you to know every word in the dictionary to answer, most likely the answer to the question is not factually accurate

#

The amount of words there really are for 5 letter arrangements of numeracy is probably not what your textbook will have the answer as

#

But if it is then I got no clue how

cyan token
#

I think your approach is the most logical, it seems unreasonable for math to expect a student to know every obscure word

thorny iris
#

Yeah that’s what I would think

cyan token
#

Do you know what the exact numerical value is if you don't mind?

thorny iris
#

6720

cyan token
#

yeah you got it right congrats

thorny iris
#

Yeah but in actuality there probably isn’t 6720 word arrangements lol

cyan token
#

scrabble says 22

alpine sable
#

can someone walk me thru this one

cyan token
#

put it through mathway

alpine sable
#

i need to learn it

#

and mathway dont even show me steps

manic quail
#

you can multiply the exponents.

alpine sable
#

so start with -2 * 2

#

then -4 * -4

#

then 16 *-3?

manic quail
#

you get 2^6 in the denominator

alpine sable
#

wait what

#

how

#

do i mulitply top and bottom by -3

manic quail
#

and 2^(-3)* something^(-4*-3) in the numerator

#

you multiply the exponent of the denominator with the exponent of the outside

ionic jewel
spiral bloom
#

In a normal distribution where µ = 100 & σ = 12, what's the probability that a random outcome exceeds 124?

#

<@&286206848099549185>

slow cargo
#

convert all the equations into y=mx+b format

#

and solve

#

pls help

thorny iris
serene moon
#

how do you solve 546x=4y*x^58/2pi * cos

#

oh also

#

@thorny iris nice pfp

misty vigil
#

hello?

#

I need help with quadratics

alpine sable
#

ok

#

just post

misty vigil
#

ok

#

and this is another question

alpine sable
# misty vigil

that's simple, no? you just do a(x-1)(x-1) which is exactly 1 root

misty vigil
#

umm

alpine sable
#

(because if you dupe a root you basically have one root no?)

misty vigil
#

im just starting pre cal

#

with a bad teacher

#

sure.......?

alpine sable
#

Do you know what's a factored form in a quadratic equation?

misty vigil
#

yes?

#

no?

#

show me

#

I think so

alpine sable
#

f(x) = (x - r1)(x - r2)

#

or something close to that

misty vigil
#

ya, so our teacher doesn't give us formulas like that, rn all we have is

#

ax^2+bx+c=0

#

@alpine sable ?

alpine sable
misty vigil
#

ah

#

all good

#

ya

#

but do you square both x and three on the other side

#

or just x

#

both no?

#

i get x=14

manic quail
#

Forget what I said, I am a moron. Isn't as nice as I thought xD

alpine sable
#

,w plot y=x^2

misty vigil
#

but answer key says 7

alpine sable
#

isnt this one root

alpine sable
misty vigil
#

we don't use graphing for this

#

at least not yet

#

wait im wrong

alpine sable
#

u could use quadratic formula to verify it if u want

alpine sable
misty vigil
#

reposting

alpine sable
#

or any other method to get zeros

misty vigil
alpine sable
misty vigil
#

yes

#

?

#

oh yeah

alpine sable
#

so f(x) = 1(0)+0x+0

#

,w 0=x^2

alpine sable
#

and x= 0

#

see 1 root

#

x=0

misty vigil
#

ah

#

smart

#

i wish there was an answer in the answer key for that one

#

but google docs is dumb

alpine sable
#

it's ok I'm in pre calc too

misty vigil
alpine sable
#

it's your function

misty vigil
#

i need someone to explain

#

it

#

but

alpine sable
#

it's 1x²+0x+0

misty vigil
#

oh

alpine sable
#

f(x) is basically y

misty vigil
#

thats my formula

#

ok

#

i see

sinful flare
#

Anyone can help me with Vector Analysis here?

misty vigil
#

isn't that physics?

alpine sable
#

(AKA: function of x which means wtf is y when x is whatever)

slow cargo
alpine sable
misty vigil
#

oh we did vectors in physics

sinful flare
misty vigil
#

this is getting cluttered

sinful flare
#

Im having a hard time figuring 10-12

alpine sable
#

yes because there are people who can't read #rules

sinful flare
#

Sorry, I'm a little desperate.

misty vigil
#

ok

misty vigil
#

what is the answer to a

#

I get 14

#

which is wrong

alpine sable
#

so you got -x²

#

(i think)

misty vigil
#

i get -x²-x+14=0

#

ah shoot

#

suppertime

alpine sable
misty vigil
#

and then divide x off

#

to get

#

-x=-14

#

/-1

#

x=14

#

ok bye

alpine sable
#

by inspection 7 is a solution to a

sinful flare
#

Anyone got any ideas how to go about my problems?

manic quail
#

@slow cargo , you already had the right idea. Here, I plotted the first one for you.

#

The overlap of the areas represents the solutions.

native remnant
#

can someone help me with this problem

#

sry the image is so tiny

ocean sealBOT
#

Chai T. Rex

native remnant
#

100a +10b + c = 47 ( a + b + c)

ocean sealBOT
#

Chai T. Rex

native remnant
#

im confused on this part

oak chasm
#

Well, it says the tens digit is half the hundreds, right?

native remnant
#

yeah

ocean sealBOT
#

Chai T. Rex

native remnant
#

b = 0.5a

oak chasm
#

Right. Now, do that for the specified relationship between the tens and the unit.

native remnant
#

b = c - 1

ocean sealBOT
#

Chai T. Rex

native remnant
#

so like 100a turns into 50b

ocean sealBOT
#

Chai T. Rex

#

Chai T. Rex

native remnant
#

a = 2b

ocean sealBOT
#

Chai T. Rex

native remnant
#

c = b + 1

ocean sealBOT
#

Chai T. Rex

native remnant
#

200b + 10b + b + 1 = 47(2b + b + b + 1)

oak chasm
#

Right.

#

Now, solve.

native remnant
#

so b = 2

oak chasm
#

,w 200b + 10b + b + 1 = 47(2b + b + b + 1)

ocean sealBOT
oak chasm
#

Right.

ocean sealBOT
#

Chai T. Rex

oak chasm
#

What's the number?

native remnant
#

423?

oak chasm
#

,w 423 = 47(4 + 2 + 3)

ocean sealBOT
oak chasm
#

Looks good.

native remnant
#

thank you

oak chasm
#

You're welcome.

cyan token
#

Question: In the word “Numeracy” how many 5 letter “word” arrangements can be made if it must start or end with a vowel?

alpine sable
#

what is a 5 letter "word" arrangement in a word?

cyan token
#

Disregard that, it’s redundant.

alpine sable
#

no really, i dont know exactly what it means lol

cyan token
#

It has to be 5 letters, and must either start or end with a vowel

alpine sable
#

,w 560 = 57 (5 + 6 + 0)

ocean sealBOT
alpine sable
#

How many possibilities are there for a vowel?

thorny iris
#

Basically you have 5 slots still. But now the first and last slots are only vowels. This question deals with addition since “or”. In numeracy there are a e u (3 vowels). So the first case is 3 x 5 x 4 x 3 x 2 and then the second case is 5x4x3x2x3

#

You get the 5 from subtracting 3 from 8 (since after you use a vowel you can’t use it again)

#

So then just add the two cases (first case where it starts with vowel, 2nd case where it ends with vowel)

alpine sable
#

,w 560=56 (5+6+0)

ocean sealBOT
alpine sable
#

Shouldnt it be 7 slots after you use 1 vowel?

cyan token
#

Thank you. I just didn’t think it made sense because that’s the exact same number as if it was to start AND end with a vowel

alpine sable
#

,w 423 =47(4 + 2 + 3)

ocean sealBOT
cyan token
#

Where as that would be 6x6x5x4=720

#

And this is the exact same sum

alpine sable
#

,w 6×6×5×4=720

ocean sealBOT
cyan token
#

Yes.

oak chasm
#

@alpine sable To play with the bot, try #bots.

alpine sable
oak chasm
#

No, click the blue link to go there.

cyan token
#

@thorny iris what would you do if the question asked for all the vowels to be together then?

alpine sable
#

5×5=25

#

,w 5×5=25

ocean sealBOT
thorny iris
#

If all the vowels had to be together in the word?

#

Like in one word together

#

It would be 1x1x1x5x4

#

but then you need to group and arrange

cyan token
#

Yeah like all the vowels had to be together all 3 of them

thorny iris
#

It would be !3x3!

#

You have 3 groups

#

5, 4, and the 3 vowels

#

And then you need to arrange 3, as the vowels can be together, but order is not specified

alpine sable
#

3×3=9

cyan token
#

3 vowels and 5 of the remaining letters?

#

No sorry

#

That’s 3 vowels and 2 remaining

thorny iris
#

Yeah so each vowel gets one spot, and then there is 2 slots remaining

#

Within those two slots are non vowels

alpine sable
#

,w 56.8³×4=

thorny iris
#

You have 5 non vowels left so you put them there

cyan token
#

Last question: What about the number of arrangements that can be made with the letter “y”?

#

That are also 5 letters

#

I assume theres more

alpine sable
thorny iris
#

So there is only 1 Y

cyan token
#

Yeah there aren’t any repeats

thorny iris
#

Since there is no order specified

#

It could be in any place

alpine sable
#

,w av

cyan token
#

@alpine sable what are u doing

ocean sealBOT
thorny iris
#

So you need to find what it is with one Y in the word, then multiply by 5

#

Basically right, Y could be anywhere in the word

#

But it can only be in 5 spots

cyan token
#

Yeah

alpine sable
thorny iris
#

So if you find what the value is when it’s in any spot

#

And multiply it by 5

#

That’s your total amount

cyan token
#

Much appreciated

thorny iris
#

Np

winged vine
#

Anybody know what i need to do here

alpine sable
#

,w 90¹+56-6=

ocean sealBOT
winged vine
#

?

alpine sable
#

,w 3x+4×2 2×-3×2=

ocean sealBOT
alpine sable
alpine sable
winged vine
#

I still don’t get that

alpine sable
#

Uggg

#

,w 3×-96

ocean sealBOT
alpine sable
winged vine
#

Ok what I’m so conspfused

#

What’s that -288 for

alpine sable
#

Negative 288

winged vine
#

Where you got what the variable was equal to

#

It’s impossible

alpine sable
#

What grade r u in

winged vine
#

9th

#

I’m in geometry

alpine sable
#

It seems like your in the 6th

#

But okay

#

I believe u

winged vine
#

I forgot got how to do those

#

I don’t even think I ever did them

alpine sable
#

It's area and perimeter

#

I learned this in the fourth grade

winged vine
#

I know

#

That it’s easy just don’t even know where do I start

#

There’s nothing on google

hardy geyser
#

someone help me the wording confused me

#

<@&286206848099549185>

cyan token
#

@hardy geyser use ratios

winged vine
#

Your correct

alpine sable
hardy geyser
#

how

#

@cyan token

cyan token
#

Actually looking at the question, that’s the right answer

hardy geyser
#

@cyan token I know but I guessed

winged vine
alpine sable
#

Easy

winged vine
#

How you solved it

alpine sable
winged vine
#

But it dosent tell me what the variable is equal to so how you took out the x

alpine sable
winged vine
#

But there not equal so you can’t use that methot of

alpine sable
#

The × is equal to times

#

Fine I got u

winged vine
#

The x is a variable

alpine sable
#

The answer is 16

#

Either 16 or 28

#

A or B

winged vine
#

Who you talking too

alpine sable
#

U

winged vine
#

Wat

#

There no multiple choice in my question

fading delta
#

can someone help me?

cyan token
#

@fading delta yes

fading delta
#

i dont understand 6 at all

alpine sable
cyan token
#

Do you know what a vertex looks like in an equation?

#

@fading delta

fading delta
#

yes

alpine sable
#

Do u think it's 16 or 28

winged vine
cyan token
#

It’s 4 @fading delta

fading delta
#

thankyou

alpine sable
#

Somebody help @winged vine

winged vine
#

Yeah

cyan token
#

Uhh what are we tryna do here

#

Solve for the area?

winged vine
#

Yeah

cyan token
#

Collect like terms

#

Ez

winged vine
#

Ohhh that’s all

alpine sable
cyan token
#

We all learn at difference paces : )

alpine sable
#

True

winged vine
#

So it’s 6x-12

alpine sable
#

Yes

#

?

#

Wait

winged vine
#

You add them or multiply them

cyan token
#

Area is LXW

#

Multiply

winged vine
#

Cuz it will be 5x+1

alpine sable
#

I believe u multiple

winged vine
#

oh ok

#

So this rigth So it’s 6x-12

alpine sable
#

12 24 36 48 60 72

winged vine
#

I put the x as 3 and solved it and then it didn’t give me the same thou

alpine sable
#

There u go

#

72

winged vine
#

Ok now I’m confused again

#

I’ll just do it like that

alpine sable
#

Basically 36+36 EZ

#

72

alpine sable
winged vine
#

Well

ocean sealBOT
gray isle
#

sum and product of roots would be the simplest way

#

also you've messed up your copmplex conjugate

#

-1 + sqrt(3)i is not the complex conjugate of 1 + sqrt(3)i

#

,w expand (x - (1+ sqrt(3)i))(x - (-1+ sqrt(3)i))

gray isle
#

results in stuff with i which isn't what you want

#

first fix your other root first

#

and then like i said

sum and product of roots would be the simplest way

#

you could expand and distribute if you want but it can get a bid tedious with all those terms

carmine lion
#

is this channel free

gray isle
#

no

carmine lion
#

alright

hardy geyser
#

did I do this right it’s x^2 right?

gray isle
#

the complex conjugate of
a + bi is
a - bi

#

whut?

#

why are you square rooting the i?

#

the complex conjugate of
a + bi is
a - bi

oak chasm
#

@mint swallow You change the sign of the part with i in it.

gray isle
#

change the sign being multiplied to the term with i from pos to neg or neg to positive

#

the complex conjugate of $\red{a} + \blue{b}i$ is $\red{a} - \blue{b}i$ \
for your question you have: $\red{1} + \blue{\sqrt{3}}i$

ocean sealBOT
#

ℝamonov

gray isle
#

no

#

what's your other complex root?

#

you really need to identify that first before you're able to move on

#

reread the tex i made above

#

and really try NOT to overthink it

#

do you understand the first line i wrote?

#

and the difference between
a + bi and a - bi

#

no

#

we still haven't even reached that point yet

#

$\red{a} + \blue{b}i$ and $\red{a} - \blue{b}i$ are complex conjugates.
can you identify the difference between them?

ocean sealBOT
#

ℝamonov

gray isle
#

for your question you have: $\red{1} + \blue{\sqrt{3}}i$ \
similarly what would be the complex conjugate of that? \
(which will be your other root)

ocean sealBOT
#

ℝamonov

gray isle
#

this is not supposed to be a trick question

#

and should take less than 30 seconds

quick token
#

how do you find the surface area of a rectangular prism

charred flint
#

whats the question

winter bay
#

@native temple bring it here

#

nvm too busy here

charred flint
#

😓

gray isle
#

the explanation for the complex conjugate has been typed like 5 times already

charred flint
#

oh

gray isle
#

what exactly don't you still understand about it

#

i've even inserted colours

#

to try and make it more clear

#

you've also even identified the difference when i prompted you

ocean sealBOT
gray isle
#

no you're jumping ahead again

#

and still not doing it properly

#

forget about x

#

completely

#

worry only about getting the complex conjugate nothing else

#

the complex conjugate of $\red{a} + \blue{b}i$ is $\red{a} - \blue{b}i$ \
$\red{a} + \blue{b}i$ and $\red{a} - \blue{b}i$ are complex conjugates.

ocean sealBOT
#

ℝamonov

gray isle
#

do you understand that? yes/no?

edgy wharf
gray isle
#

well that's the definition of the complex conjugate

#

as mentioned/implied multiple times by multiple people

#

to get the complex conjugate, you change the sign in front of the imaginary term form pos to neg (or from neg to pos)

ocean sealBOT
gray isle
#

not the issue here
though the difference of two squares is the reasoning behind why conjugate root theorem is applied to get a polynomial with real coefficients

#

this is purely about getting the actual conjugate nothing else

#

$\red{a} \underbrace{+}_{\text{to get the complex conjugate, change this to a -}} \blue{b}i$

ocean sealBOT
#

ℝamonov

gray isle
#

alternatively if you have: \
$\red{a} \underbrace{-}_{\text{to get the complex conjugate, change this to a +}} \blue{b}i$

ocean sealBOT
#

ℝamonov

gray isle
#

that's all i wanted

#

my numbers are a and b

ocean sealBOT
gray isle
#

no

#

stop fking skipping ahead

#

because it's pointless if you don't get the first step correct

#

if by IT you mean the sign being applied the the part with i
yes, you change that to get the complex conjugate

#

you really shouldn't be overthinking this

ocean sealBOT
gray isle
#

no

#

stop fking skipping ahead
because it's pointless if you don't get the first step correct

#

forget about x

#

at this point completely ignore that variable or any other part of the question

#

no

#

not even that

#

focus only on finding the complex conjugate of
1 + sqrt(3)i

#

currently I'm only after the very FIRST step ONLY nothing else

#

the complex conjugate of
1 + sqrt(3)i is:

#

and the complex conjugate is the only thing I want to see.

#

no extra crap

#

no skipping ahead

#

no xs

ocean sealBOT
gray isle
#

i mean still fkn skipping ahead...

#

but apart from the missing parentheses at the end

#

you actually did it properly

#

your complex roots are
1 + sqrt(3)i and 1 - sqrt(3)i

#

and to expand the above, you could distribute but that can get tedious

#

alternatively you can use the sum and product of roots which will make this a lot simpler

ocean sealBOT
gray isle
#

(x - p)(x-q) = x^2 - (p + q)x + pq
the value of (p + q) should be very easy to obtain
and pq will just the difference of two squares

#

also wait

#

since i was a bit pissed

#

i overlooked where your square roots were

ocean sealBOT
gray isle
#

the radical shouldn't extend over the i

#

wdym by key

#

sqrt(3) is just a number

#

wdym

#

as stated multiple times

#

conjugate root theorem
and definitiion of the complex conjugate

#

by DEFINITION, the COMPLEX CONJUGATE of a + bi is a - bi

#

by (complex) conjugate root for your polynomial to have real coefficients,
if a + bi is a root, a - bi will also be a root

#

here you are told that
1 + sqrt(3)i is a root
and by that theorem (conjugate root theorem)
1 - sqrt(3)i will also be a root
(since if you were to compare 1 + sqrt(3)i to a + bi the a=1 and b=sqrt(3)),

#

does that make sense so far?

#

yes. as stated almost 10+ times already, those are complex conjugates

#

and for the past two hours that was literally all i wanted you to apply

#

regardless, does everything that I've just typed make sense so far?

#

ok.

#

now you wanted to expand your factors with complex roots
$$(x - (1 + \sqrt{3}i))(x - (1 - \sqrt{3}i))$$

ocean sealBOT
#

ℝamonov

gray isle
#

expanding normally can be a bit tedious, so you can consider the sum and product of roots

#

consider:
$$(x-p)(x-q) = x^2 - (p+q)x + pq$$
where:
$$p =1 + \sqrt{3}i$$
$$q =1 - \sqrt{3}i$$

ocean sealBOT
#

ℝamonov

gray isle
#

yes, but its more tedious

#

what i just wrote

#

instead of manually expanding
(x - (1 + \sqrt{3}i))(x - (1 - \sqrt{3}i))
consider what happens when you expand
(x-p)(x-q)

#

then consider the values of your roots

#

their sums and products are relatively easy the calculate

ocean sealBOT
gray isle
#

yes

#

(x+5)(x - (1+ sqrt(3)i))(x - (1- sqrt(3)i)) does indeed expand to that

#

though you should consider a scaling factor (to be determined using f(-2) = 36)

outer plaza
#

i have this question quys

#

how do i work it out?

#

could someone message me privately

#

yeah totally doing a test while in discord...

#

i live in Australia, our classes are in person lol

#

im so confused

#

what?

#

anyway

#

i mean i didnt know helping with studying was cheating

gray isle
#

be more civil

outer plaza
#

but i guess this is the wrong place then

tame shell
#

don't use sarcasm wrt cheating

#

people will 100% take it the wrong way

#

as people who do attend in person classes still cheat @outer plaza

outer plaza
#

idk how this goes in the US or wherever you guys are from

#

our teachers take our phones before our exam

#

and we put our bags at the front of the room

tame shell
#

lol I wish they did that

gray isle
#

some places do tests online and it may be hard to confirm that
there are concerns when people specifically request for stuff to be dealt in dms immediately

tame shell
#

yeah

outer plaza
#

i want it in DMs because i wanted to be walked through it

#

and not clog up this channel

gray isle
#

so if you want help you should be able to get it within this server, there are plenty of free channels to use, that's what they're for

outer plaza
#

i literally wanted to ask questions and go over some stuff in details because i just dont get it. I have used the Python Discord and The Cisco discord to great success with many helpful people hopping in chats with me sharing their screen and walking me through some stuff i just dont understand. i understand i have more leeway in those discords as ive been in them for a while, and i just entered this one.

#

However its definitely not very welcoming when the first people you have messaging you are people like NDY, Why tf would i feel comfortable in this server when i have people accusing me of doing things from my very first msg

sly mantle
#

@mint swallow can stand to soften their tone toward other users, even users who they think are breaking server rules. heads up however @outer plaza this server takes academic honesty very seriously, and as per universal laws of online chats, if there's potential for sarcasm to be taken seriously, it WILL be taken seriously by someone

alpine sable
outer plaza
#

i read the rules lol

#

no cheating during exams

#

i also asked how do i work it out

lost geyser
#

what does it mean basic geometry

gray isle
#

no calculus

#

use formula for areas of basic shapes

lost geyser
#

so like what is 'area bounded' even asking for then

#

im not quite sure

#

this is riemann sums, should i just find the area for each rectangle without the formula

#

is that what its asking essentially?

gray isle
#

yes

lost geyser
#

i see.

gray isle
#

pretty much

lost geyser
#

so b x h = a

#

okok

gray isle
#

not quite what you should apply here

#

the region bounded here isn't a parallelogram

lost geyser
#

so how would i find the are abounded then

gray isle
#

have you drawn a pic?

lost geyser
jagged imp
#

huh no not rectangles, think triangle

gray isle
#

the question you posted doesn't really involve reimann sums

lost geyser
#

iinteresting

#

because the question i posted is relating to riemann sums, let me show you the previous question

wicked ember
#

yes but

gray isle
#

regardless the part you posted does not

wicked ember
#

however here they want you

#

to use basic geometry

gray isle
#

the full region will be a simple trapezium

wicked ember
#

here it’s clear to see you can find the exact area

#

just with area of trapezium

#

or trapezoid if that’s what you call it

lost geyser
#

okay wait i think im understanding it

#

so take out the rectangles, find the area between the x axis and the line that was given

#

but on the intervals 1, 4

wicked ember
#

no here don’t use rectangles

#

again they gave “using basic geometry”

#

no Riemann sums

lost geyser
#

yeah i said throw the rectangles away, i outlined the part in red, im just finding the area for that?

#

or am i completely misinterpreting this

gray isle
#

assuming those boundaries are at x=1 and x=4, that's pretty much it

lost geyser
#

ah okay, they are

gray isle
lost geyser
#

yep yep i understand that now

#

have you found a solution for it?
the answer i worked out to is 30, not sure if thats correct

#

disregard my 30

#

24 was my new answer

gray isle
#

neither is what i'm getting

obsidian plover
#

i found z as 40

#

i want to know if i am correct

#

the 220 means degrees

gray isle
#

you should probably label the lengths of the sides you're actually using.
i suspect you made an error with the length of the edge that's at the x-axis

lost geyser
#

oh

#

its 1, 4

gray isle
#

i suspect you made an error with the length of the edge that's at the x-axis

lost geyser
#

oh my god

gray isle
#

🙂

lost geyser
#

21?

gray isle
#

no

lost geyser
#

oh because i got to recalculate the triangle

#

18 final answer

gray isle
#

yeh

#

@obsidian plover no. your values are incorrect

obsidian plover
#

let me try again

gray isle
#

show work and reasoning when you do

obsidian plover
#

e has to be 40 due to 360-220=140, and ae and ec are tangents so arc ac and aec have to be supplementary

gray isle
#

yes

#

though you should really be using capitals

#

and clearly mention that
360-220=140 gets you the measure of arc AC

obsidian plover
#

alright

safe bison
#

Hi,

I've got this problem
u < 4 / u-3

What's shown as the correct way to do this is
u - 4 / u-3 < 0
(u^2 - 3u - 4 )/u-3 < 0
(u-4)(u+1)/u-3 < 0

But if I tried it this way
u < 4 / u-3
u (u-3) < 4
u^2 - 3u - 4 < 0
(u-4)(u+1) < 0

the denominator is just straight up gone, what went wrong here?

gray isle
#

um...

#

do you have a pic of the work?

#

it feels like there's a gross disregard for parentheses

#

that makes it near impossible for me to follow

tight locust
#

@safe bison nothing is wrong

#

both are correct lines of reasoning

#

the first one is just missing an extra step

#

(u-4)(u+1)/u-3 <= 0, so (u-4)(u+1) <= 0

#

the difference being that u cannot be 3

#

which you should account for

gray isle
#

is that u-3 supposed to be part of the denominator?

#

if yes, you really should be writing (u-3)

tight locust
#

it's pretty obvious if you look it for a sec

gray isle
#

spacing is not a substitute

#

spacing means nothing to me

#

anyway the second method is wrong (without proper justification)

tight locust
#

right because you'd have to split into cases

gray isle
#

since it is unclear what the sign of (u-3) is, you can't just assume that its positive and that the direction of the inequality won't be affected

#

and you'd have to explicitly state the extra work that's going to be involved which is a pain

tight locust
#

is there a sign that means equal OR not equal to

#

like if x >=0 and x <=0

gray isle
#

i mean you could use $\overset{?}{=}$ to indicate something to be determined

ocean sealBOT
#

ℝamonov

gray isle
#

which could be used to do some proofs or ultimately disprove something

alpine sable
#

how do i find the 50 degrees on the top left?

#

i'm supposed to use it to create a vector triangle and solve for $V_a$

ocean sealBOT
#

MyMethLab

alpine sable
safe bison
alpine sable
#

Hi

#

The 7th word is combined

#

I got this

#

,rccw

ocean sealBOT
alpine sable
#

<@&286206848099549185> sorry for ping I gtg to school

ocean sealBOT
alpine sable
#

just need to confirm the answer

#

I'll check in 25 mins

#

@coral pagoda ?

lost geyser
#

question e, included question b in reference

vale wigeon
#

f(x)=x^2+1 is a parabola, so the region whose area you get is not a polygon nor is it made of polygons and circles

lost geyser
#

that makes sense

timber geyser
#

i need help with part of a question, im trying to find the area of the triangle FOC, i used the formula 1/2xbxh cus its a right angle but in the MS they used 1/2absinC, and there answer came out different to mine. why cant i use 1/2bxh for this?

half lotus
#

i need help with ti82 calculator

#

idk how to use the lim function and cant find anything online

#

like lim x -> infinite

#

how do i input this into calc

timber geyser
#

@half lotus plz get free channel

olive vale
ocean sealBOT
#

morpheus

timber geyser
#

im not sure what you mean, is my method correct?

olive vale
#

yeah you can very well use 1/2 bh

#

What's the answer you got and what's the answer they got?

timber geyser
#

one sec lemme find it

#

here is their calculations for that part

vestal hawk
#

guys how to express a sine and cosine wave as a single sine wave?

timber geyser
#

@olive vale i did 1/2 x4x12 to get 24

#

the value for r is given as 4 and the raidius CA is 12, theta is given as pi/6

olive vale
#

area of FOC is 1/2 (OF)(FC) and not 1/2(OF)(AC) like you seem to have done

timber geyser
#

oh right yes, FC is 12-4

#

right?

#

wait no

olive vale
#

no

#

FC is $r/tan(\theta)$

ocean sealBOT
#

morpheus

timber geyser
#

ahh right

#

i confused the height with the radius

#

ok i get it now, thankyou!

olive vale
#

no worries

tiny field
#

Decide the equation for the tan in the points which (picture) cuts (y=x+1)

#

How should i proceed with this one, im supposed to use derivates

dense mirage
#

Is the boxed answer right? Or is it suppose to be negative

zealous igloo
#

Someone pls help

wicked ember
#

try to use quadratic equations

#

that’s my best guess

dense mirage
#

Anyone?

wicked ember
#

and both h and c are positive

dense mirage
#

Why do I get a negative answer In my calculator

#

I did the top first

#

Then divi3d

zealous igloo
dense mirage
wicked ember
#

for example

wicked ember
#

because h is positive

#

c is positive

#

and |E| is always positive whether or not E is negative or positive

#

I mean they can be 0 but they aren’t

zealous igloo
wicked ember
#

look at the picture I drew just now

#

try to come up with quadratic equations

#

or if you want

#

you can have a circle as well

#

it really depends on what you want

#

just need to find two non linear equations

dense mirage
#

So |E| is positive even if it's negative?

#

Bru wdf

wicked ember
#

no

#

basically

#

E is negative

#

however

#

since it’s in an absolute value

#

|E| is positive

dense mirage
#

Wdym bby absolutely value

wicked ember
#

|x| means the absolute value of x

#

or in order words

#

the magnitude of x

#

basically it’s x if x>=0

#

and -x if x < 0

zealous igloo
#

Also my bad for interrupting

wicked ember
#

it’s fine

upper yarrow
#

anyone know the proof of this?

pale cargo
#

Why is this wrong^^^^?

#

Or why do I feel like its wrong?

dense mirage
#

@wicked ember so if it has | | around it and it's negative it's basically positive?

wicked ember
#

yep

daring chasm
#

it's a bit more wonky than that with complex numbers, but otherwise yeah

terse iron
#

am i doing this correct

alpine sable
#

How do I answer this?

#

ok thanks

#

Proposition

#

Conditional and Biconditional

#

discrete math

shell widget
#

@alpine sable you cant think of anything?

alpine sable
#

No I mean

#

how can I answer it?

#

like uhm

shell widget
#

Okay so i'll do the first one

alpine sable
#

A false implication with a false conclusion.
My Answer: John did not do his homework, therefore he will fail his grade?

#

It doesn't provide me anything 😦

#

I did that that as well

shell widget
#

we cant say anything about that implication

alpine sable
#

I know proposition

#

but what does this question defines.

shell widget
#

Listen

alpine sable
#

my classmates did explain this but it did not give "example"

#

explain like that's the answer

shell widget
#

A implication P --> Q (where Q is false) is false when P is true

#

Do you know that?

alpine sable
#

but mine is different?

shell widget
#

first answer mine

alpine sable
#

from what I understand false implication is p is 0 and false conclusion is q is 0 meaning p implies q 0 0 1

vale wigeon
#

i was summoned

#

what are we discussing

alpine sable
#

Propositions

shell widget
#

@novel field Please leave if u cannot help

vale wigeon
#

can i see the original problem/question/whatever

shell widget
vale wigeon
#

@terse iron channel busy please move

terse iron
#

my bad

vale wigeon
#

P->Q is false if and only if P=1 and Q=0

#

otherwise its true

#

this lets us eliminate some of these points as impossible

alpine sable
shell widget
#

dont ask me, ask ann

#

Im out

vale wigeon
#

number 4 is impossible

#

none of the others can be ruled out immediately

alpine sable
#

O.O

vale wigeon
#

for an implication to be false you need a true hypothesis and a false conclusion

alpine sable
#

Wait so is it just like this then?

vale wigeon
#

do you want me to go through each of the other five things and give an example for each

#

just like what

vale wigeon
#

1, 3 and 5. ok

alpine sable
#

I'm an odd number my homework

alpine sable
# vale wigeon just like what

A false implication with a false conclusion.
My Answer: John did not do his homework, therefore he will fail his grade?

vale wigeon
#

that's number 1

alpine sable
#

So wait it is correct?

vale wigeon
#

and i'd say "if john doesnt do his homework he will fail his grade"

#

and under the assumptions that john actually DOES do his homework and actually passed his grade

#

this will be suitable for number 1

alpine sable
#

A false implication with a false conclusion.
My classmates answer: "The whole explanation of this"

vale wigeon
#

lmfao

vale wigeon
#

what

#

wait hold on

alpine sable
#

ok

vale wigeon
#

i misread shit

#

lmao

#

god

alpine sable
#

XD

vale wigeon
#

the words

#

argh

alpine sable
vale wigeon
#

"john didnt do his homework" need not be false

#

like

#

we dont actually know if this john person did or didnt do their homework yknow

alpine sable
#

Ok I don't get it in number 1

#

<@&286206848099549185> help?

dense mirage
#

Is this right

#

@wicked ember

wicked ember
#

if you did the calculation right yes

dense mirage
#

I think I did

visual stream
#

is there a question being asked

desert comet
#

my bad

#

ill move channel

visual stream
#

how do you do this

vale wigeon
#

have you ever completed the square before?

visual stream
#

yea

#

but not with a coefficient

#

theres a coefficient of 6 rn

#

idk what to do

vale wigeon
#

yeah

#

you can get rid of it

visual stream
#

divide everything by 6?

vale wigeon
#

yup

visual stream
#

yeah i tried that and something went wrong in the middle lol

manic glade
#

weird question but whats the english term for placing something in a formula

visual stream
#

substitution?

manic glade
#

if x=a+b and you have y=x+3

#

so you do y=a+b+3

#

substitution for ^ ?

visual stream
#

yeah subsitution

manic glade
#

alright thanks

#

pretty annoying we learn math using the local language instead of at the very least english if not proper formal logic

alpine sable
#

@vale wigeon Are you available to help? 😅

vale wigeon
#

i dont think i am, sorry

#

i keep getting tongue-tied every time i try to do that proposition shit

alpine sable
#

Ok I don't understand tongue tied? 😅

#

u got this

vale wigeon
#

is * a group operation?

manic glade
#

yes

#

also if it is legal , what exactly is the justification for line 2

alpine sable
#

multiplying on the right by a constant is a function

manic glade
#

a simpler explanation maybe? we didnt get to functions yet

vale wigeon
#

you multiplied by b^-1 on both sides

manic glade
#

yeah but why is that something i can do in general, is there some fancy term for that?

#

if x=y why is x+3=y+3

vale wigeon
#

because addition is a function

#

or otherwise, why wouldn't it

alpine sable
#

x=y means intuitively that x is the same thing as y

#

ìf you add 3 to the same thing you get the same result right

#

ie 1=1 and 1+3=1+3

manic glade
#

so nothing fancy like "associative/commutative" ?

vale wigeon
#

is there really a need to be fancy thonk

manic glade
#

no idea ^^

alpine sable
#

the reason is because its a function.. but you said you dont know that

manic glade
#

alright, and i can just describe it as multiplying despite the operation being nondefined?

alpine sable
#

its just a name

vale wigeon
#

yeah like... youre denoting it with an asterisk

#

theres only one operation anyway

pulsar willow
#

Can anyone tell me if this is wrong solution

#

The 2^(x+4) in original equation is 2^(x+2) on the Note that lines

alpine sable
#

check the values they get back in original equation

pulsar willow
#

Yes it doesn't match up the x value, it must've been wrong. Thank you

vale wigeon
#

Because of + in equation, it is not useful to take log of both sides.

#

remove this, this line is entirely unnecessarsy

#

also yeah 2^(x+4) vs 2^(x+2)

worn jetty
#

Quick linear algebra question

#

So I have a nilpotent endomorphism of a vector space E with a nilpotence indice of p

#

(in other words : f^p = 0 and f^(p-1) != 0 )

plain lion
worn jetty
#

we are tasked to show that if rank(f) = n-1 (where n = dimE) then for all k in {0,..,n} ; dim Kerf^k = k

#

but no matter how I look at it it just feels wrong

#

because clearly dim Ker f^p = n, but p doesn't necessarily equal n

#

yes, so my question is.. if the rank of a nilpotent linear application is n-1

#

does it imply that the nilpotency index is n ?

#

if not, what would a good counter example be ?

alpine sable
#

i think its true actually, if you look at jordan form all superdiagonal entries will be 1

worn jetty
#

hmm.. I'll look into it more

#

but interestingly

#

I was searching on google for something similar

#

and I found a pdf

#

that our maths professor ripped

#

for this homework problem

#

: )

#

and it stated that p = n

#

: )))))

#

and it asked to show that rank(f) = n - 1

#

then this question

#

so yeah...

alpine sable
#

i tried to construct counterexample but run into trounle cuz

#

since the rank is n-1

#

at each step only one dimension goes to null

#

and if you mapped more than one dimension to that one

#

then rank would automatically decrease more

worn jetty
#

Hmm

#

I see

#

give me like.. 10 minutes

#

If I come up with some counter example I'll share it here with you, I'll try working through it again

#

thanks for your time though ! I appreciate it a lot :3

alpine sable
#

due to Jordan form it should be impossible tho, if you know jordan

#

i think could convert my argument to proof but am lazy lol

worn jetty
#

haven't actually studied it in class yet but I worked through problems with it

#

haha, I get that !

ebon cliff
#

How do u solve questios like this

alpine sable
#

Well, what does it mean for two lines to be perpendicular?

ebon cliff
#

like lines which aren't vertical intersect and form a right angle

alpine sable
#

what does it mean for two lines to form a right angle?

ebon cliff
#

The lines are perpendicular

alpine sable
#

that is circular reasoning

#

Have you ever heard of the dot product?

ebon cliff
#

No

#

ah yes that

#

like c x c = (a-b) ( a-b)

#

Right?

alpine sable
#

i have no idea what you mean by that

ebon cliff
#

oh

#

ok

alpine sable
#

dot product of vectors

ebon cliff
#

Let me search it up

#

I dont think I've learnt about it

jagged imp
#

i feel like this is probably supposed to be done with the fact that 2 lines are perpendicular iff the product of their slopes is -1

ebon cliff
#

I though we would have to draw the line

#

from the two points we have

alpine sable
#

oh that would make sense 111..

ebon cliff
#

and work frmo there

alpine sable
#

drawing is not a proof

ebon cliff
#

ok

alpine sable
#

but i guess you could do that

ebon cliff
#

it would take too long wouldn't it because we would have to grpah each line

#

and we are meant to do questions like these in 30 secs in the exam

alpine sable
#

did you learn about slopes

ebon cliff
#

kind of

#

Like I have a brief Idea

#

but need to improve a lot in linear

ripe ginkgo
#

Got a linear system with a sparse matrix, the spy/sparsity plot of A looks like this:

#

b and x are fully dense

#

any good ways to factorise/solve a system with this sparsity pattern?

#

similar matrix generated for the problem with n=5 (first matrix is for n=250)

alpine sable
#

I have a few questions, 38 and 39 that I need help with. I'm not too sure how to do them, as we were never taught how

#

It's integration, but I just don't know the method. Any ideas?

indigo jetty
#

it's just direct integration

#

for 39 u can expand first before integrating

alpine sable
#

yeah

#

i integrate, then what?

#

What is the point of them giving me y and x values?

#

Because, I checked the answers at the back of the textbook and I got a different result from just integrating and leaving at that compared to what they did

#

And they don't have worked solutions

indigo jetty
#

so what do you get when you integrate 3x^2 - 1?

alpine sable
#

x^3 - x

indigo jetty
#

you are missing a term

alpine sable
#

oh yeah + C

indigo jetty
#

yes

alpine sable
#

x^3 - x + C

indigo jetty
#

now do you know why they give you x and y?

#

because you need to solve for C

alpine sable
#

AH ok

#

so i plug x and y in, solve for c and put c back into the equation

indigo jetty
#

yes

alpine sable
#

thank you

indigo jetty
#

and that will be the answer

alpine sable
#

Can someone help me with this

alpine sable
#

What does In mean In matrix?

glass lichen
alpine sable
alpine sable
glass lichen
#

Never seen that notation

#

Probably just applying the row operation

alpine sable
alpine sable
glass lichen
#

Or it's their notation for the ele. Matrix associated with the operation

alpine sable
#

Ok

alpine sable
#

Hello. I have confusion about these 2 questions. For the 1st one my answer was -(100/q - 1) using p/q/dp/dq.

Did I answer it correctly? Shouldn't point elasticity be a number?

#

Excuse me kindly see that my question hasn't been answered yet. Please ask yours in another channel.

vale wigeon
#

you got the point elasticity formula wrong, it's (p/q)/abs(dp/dq)

#

which would give you $\frac{100}{q} - 1$ as your point elasticity

ocean sealBOT
vale wigeon
#

and the elasticity being a number is not really an issue. it's different at different values of the demand after all

alpine sable
#

I see. Thank you very much.

alpine sable
#

3 units would cost $1.20, offer being 3 for $1, you save 20 cents
and with the offer, 12 units would cost $4, whereas without the offer $4.80, in this case you save 80 cents

alpine sable
#

24 units with the offer would be 8 (you do 24/3 * 1 = 8) and without the offer 9.60 (24*0.4)

pallid acorn
vale wigeon
#

the coefficient of x is the number attached (multiplied) to the lone x term in the polynomial

hasty quail
#

so 2

tired cave
#

can someone help me with finding a phase spectrum in Fourier series ?
I am getting completely different values than my friends, I don't know what I'm doing wrong

vale wigeon
#

yeah but it was supahotfire's job to do that, not yours @hasty quail