help-0

[acoustic valve]

i literally said it was helpful on occasion

i have never been rude in this server

[ionic jewel]

ur good i was mostly mad at the other guy

[elfin hazel]

Since it is a closed system, center of mass in X position and Y position remains constant

i believe this is more of a physics than *mathx question, you could post it in the physics discord instead

[split summit]

Hi i have an excel question

[lusty jasper]

guys

please

help

[ocean seal]

Chai T. Rex

[lusty jasper]

yes

figured it out

[oak chasm]

Oh, what did you get?

[lusty jasper]

my teacher is helping

lol

[oak chasm]

Oh, OK 🙂

[spring spruce]

"If sin A is 0.865 what is angle A"

guys is there a formula for how to do this question
?

[ocean seal]

Chai T. Rex

[spring spruce]

i see

thanks

[ocean seal]

Chai T. Rex

[oak chasm]

No problem.

[spring spruce]

got 59.88

[oak chasm]

,calc asin(0.865)*180/(pi)

@spring spruce How did you get 59.88?

[brave solar]

1 rad = 180 degrees

[oak chasm]

@brave solar No.

[brave solar]

oopss

sorry

pi rad =1 80 degrees

[ocean seal]

Result:

59.882705252678

[spring spruce]

wait how do i use the bot

[oak chasm]

@spring spruce You were right.

[spring spruce]

do i just put

,

before it

[spring spruce]

oh okay ty

[oak chasm]

@spring spruce ,calc whatever

[spring spruce]

thanks

[oak chasm]

Though, remember that it uses radians.

[spring spruce]

k

[charred heron]

so

[split summit]

i got another cute question

[charred heron]

oh

[split summit]

In a jar on my desk, I have 5 black ink pens, 3 green ink pens, 4 red ink pens and 3 pencils. If I absent-mindedly reach up, without looking and grab one and start writing, what is the probability that it will be a black ink pen?

[charred heron]

what do you think ?

how would you approach the question?

[split summit]

multiply them all together first then i have no clue

[charred heron]

why multiply ?

[split summit]

im guessing i should add then

[charred heron]

no i wasnt objecting

i was just asking

to understand your thought process

[split summit]

i just thought it was combining them all together

its how ive solved other prob quesitons

[charred heron]

so how would you use that number?

[split summit]

i think i have to find the chance i will grab one of the five out of 15

[charred heron]

yeah

[split summit]

so what do you think

[charred heron]

so

theres 15 total things in the jar

5 of them = black ink pens

out of the 5 black ink pens

we select 1

thats the information given

[charred heron]

try to form an expression of that

[split summit]

i got et 5/(5+3+4+3) = 5/15 = 1/3

[charred heron]

alright

that is correct

1 in every 3 'objects' in the jar is a black ink pen

so therefore the probability of u selecting a black ink pen at random would be 1/3

[split summit]

yep

[main gate]

What does this mean?

I know what the n represents, just unsure about the sigma and the i on the right

[brave solar]

whats "this" here

sigma means summation

i is the symbol thats varied in the summation

[oak chasm]

@main gate The sigma is a summation. $$\sum_{i = 0}^{3} i = 0 + 1 + 2 + 3$$

[brave solar]

and $| i \rangle$ usually represents vectors

[ocean seal]

Chai T. Rex

PROnoob

[main gate]

Ahh, okay

[ocean seal]

Chai T. Rex

[main gate]

So does this mean the summation * vector i?

[oak chasm]

No, that vector stuff is inside the summation.

[main gate]

Ohhhhh

[ocean seal]

Chai T. Rex

[oak chasm]

Same idea.

[main gate]

This makes sense now, thanks

[oak chasm]

No problem.

[tight locust]

i^2 = -1

this simplifies to -(1+x) where x is the upper bound

[split summit]

i have a cute lil question
[9:18 PM]
Find the area under the standard normal distribution for Z = -.5 and Z= + .5.

Find a Z score that has 95% of the population less than (to the left of) it.

[tight locust]

9:18 PM

[split summit]

sorry i asked this question somewhere else

[tight locust]

Lmao!

[split summit]

im real bad at this stuff

[tight locust]

me too

i've never taken stats

[hardy geyser]

<@&286206848099549185> how is it 26

[little cape]

what is (3x)^3

[hardy geyser]

27

[little cape]

do you mean 27x^3?

[hardy geyser]

yes

[tight locust]

indeterminate. you are not given the domain of x

[little cape]

so you have (27x^3 - x^3)/x^3

[hardy geyser]

yup

[little cape]

what is the numerator equal to

[tight locust]

it simplifies to 0/0

[little cape]

this obviously does not need that amount of evaluation

[tight locust]

but i suppose it all works out if you take the limit.

[hardy geyser]

27^3 - x^3?

[tight locust]

C \ 0 should be the domain

[little cape]

yes

simplify that

[tight locust]

and that's also not correct.

[little cape]

please dont interrupt this with knowledge that isnt needed right now

[tight locust]

(3x)^3 is not equivalent to 27^3

[little cape]

the question is simple algebra, so we're obviously not supposed to check if its continuous

[glass lichen]

@tight locust you're just being a distraction at this point

[hardy geyser]

27x^3 - x^3 = 27?

[tight locust]

omg

what is (3x)^3?

[glass lichen]

Let El help

[little cape]

@tight locust please stop

[alpine sable]

its 26

[tight locust]

you're telling him false information.

[glass lichen]

Bruh read what you wrote End

[little cape]

27x^3 - x^3 = 26x^3.

[glass lichen]

None of what you said pertained to the question, end of story

[alpine sable]

$(3x)^3 = 3^3 x^3$

[ocean seal]

square

[hardy geyser]

@little cape how come it’s not just 27 ?

[tight locust]

ok i guess (3x)^3 is equal to 27^3 now

[little cape]

there is an x as well

[tight locust]

thank you

[little cape]

look at what @alpine sable said above

(3x)^3 = 3^3 * x^3

[alpine sable]

$27x^3 - x^3 = 26x^3$

[ocean seal]

square

[hardy geyser]

wait how come it minus 1 now cancel out just the x^3

[little cape]

that is incorrect.

[hardy geyser]

this how I was thinking

[alpine sable]

what

u cant do that

[hardy geyser]

wait why

cause 27 attached?

[little cape]

4(3) - 3 is not 4. (this is according to your logic)

[alpine sable]

$\frac{26\cancel{x^3}}{\cancel{x^3}}$

[ocean seal]

square

[alpine sable]

=26

[glass lichen]

ok now dont do the question for them

[hardy geyser]

@alpine sable u can only cancel if it’s dividing?

[little cape]

4(3) - (3) = 3(3) = 9

according to your logic, 4(3) - 3 = 4 which is obviously not true

[alpine sable]

there are many instances where you can cancel out things, $27x^3 - x^3$ is not one of them

[ocean seal]

square

[little cape]

27x^3 is just 27 multiplied by x^3. they are not 2 separate terms.

if it was 27x^3/x^3, you would be able to cancel

but not in this case

[hardy geyser]

oh ok since it’s subtraction you do it differently same goes with addition too?

[little cape]

yes

[hardy geyser]

Thank you

[coral pagoda]

The good news is 27x^3 and -x^3 are like terms, so we can combine like terms by adding the coefficients

[alpine sable]

$\text{da grind} \to \text{da bag}$

[ocean seal]

square

[coral pagoda]

I'm not even gonna ask

[split summit]

Find the area under the standard normal distribution for Z = -.5 and Z= + .5.

Find a Z score that has 95% of the population less than (to the left of) it.

[hardy geyser]

<@&286206848099549185> how is it D I only count 7?

[oak chasm]

@hardy geyser Write 00000000003.2. Move the decimal point left eight places.

What do you get?

[hardy geyser]

I just fussed b

Guseed

[oak chasm]

OK.

[coral pagoda]

@oak chasm gave you a perfectly good way to find the answer. So stop guessing,solve, and make sure you get the right answer

[quiet lantern]

Can someone help me understand how this is calculated, whenever I try to calculate the numerator, I get 30 / 6 = 5

apparently their numerator is about 44

[gray isle]

are you familiar with the base definition of the absolute value?

[quiet lantern]

no

The only thing that I know is that anything within | -X | = X

negatives turn into positives

[gray isle]

$|x| = \begin{cases} x \ &\text{if } x > 0 \
-x \ &\text{if\ } x\leq 0 \end{cases}$

[ocean seal]

ℝamonov

[gray isle]

so, depending on whether the insides of your absolute values are positive or negative, adjust the signs appropriately and express them without abs values to make simplicfication easier

[ocean seal]

Chai T. Rex

[quiet lantern]

Ahhh, I think I understand. So I did

| - 7 - 7.3 | = 0.3

but I'm supposed to make it 14.3 ?

I turned the -7 to 7 because its within absolute brackets, is that wrong?

[gray isle]

you should note that 7.3 is present multiple times in the question, so its intended that you don't actually explicitly calculate each thing individually but instead find a better way to simplify everything

[gray isle]

for | - 7 - 7.3 |, the inside, -7-7.3 is clearly negative and by definition,
| - 7 - 7.3 | = -(- 7 - 7.3) = 7 + 7.3

apply a similar idea for all the other terms

[idle elbow]

<@&286206848099549185>

[gray isle]

note, it'd be much easier if you don't actually combine the 7 and 7.3

[quiet lantern]

Thank you very much! So I should solve the equation inside (regardless of their sign) before turning it into positive

[gray isle]

if you do everything properly all those 7.3s will cancel, avoiding the need to do tedious calculations

[quiet lantern]

I see! Thank you for your help

[gray isle]

Thank you very much! So I should solve the equation inside (regardless of their sign) before turning it into positive
very bad wording

[quiet lantern]

Oh

[idle elbow]

@gray isle can you please help me

[gray isle]

#❓how-to-get-help don't ping helpers immediately, don't ping specific people without their permission

[idle elbow]

Oh

I just joined

My fault

[sly mantle]

@solar glacier read #❓how-to-get-help, don't multipost

[floral trail]

is using the tangent correct here?

[alpine sable]

yes

[floral trail]

ok

so i did tangent of 41 degrees = 7.8/X

[alpine sable]

how are you going to get x now

[floral trail]

which X

the equation or triangle

[alpine sable]

x m your missing side

you've made an equation using tangent

now you need to solve for x

in other words isolate x

[floral trail]

ok wait

do you multiply tangent of 41 deg x 7.8

and get X

[alpine sable]

no

the equation you made before is $tan(41)=7.8/x$

[ocean seal]

sxkura

[ionic jewel]

$\tan(41) = \frac{7.8}{x}$

[floral trail]

yes

[ocean seal]

bunny

[alpine sable]

now you need to get x on one side on its own right to find what x is

[floral trail]

do you multiply tang 41 x (x)

[alpine sable]

so lets multiply both sides by x that way x will be on the left and it isn't in a fraction anynore yes?

yes

u do that

[floral trail]

tan41 x (x) = 7.8

[alpine sable]

yes now what do u do

to isolate x

tan (41) is being multiplied by x how do we get x on its own

[floral trail]

divide by x

[alpine sable]

let me rephrase that

x is being multiplied by tan 41

how do we get x on its own and tan 41 to the other side

the inverse of x being multiplied by tan41 is

...

[floral trail]

divide by tan41

[alpine sable]

yes

then we have $x= tan41*7.8$

[floral trail]

ok

[ocean seal]

sxkura

[ionic jewel]

using x as a variable and multiplication symbol might be confusing

you should use the \cdot latex command

[alpine sable]

how do u do that im so bad at texit

i only just joined lkke a week ago

[ionic jewel]

$x = \tan(41)\cdot7.8$

[ocean seal]

bunny

[alpine sable]

ok thank u

[ionic jewel]

although normally we would put the 7.8 in front with no symbol

continue tho sorry to interrupt

[alpine sable]

now you can get what x is by putting tan41*7.8 into a calculator and then you have the missing side

[floral trail]

1.253 m

[alpine sable]

,w tan(41)*7.8

[ocean seal]

Results provided by WolframAlpha

Click here to refine your query online
Upgrade to WolframAlpha Pro!

Requested by sxkura#6731

[floral trail]

6.780

yep

6.8 m

then

[alpine sable]

just make sure you say what you rounded to

when you put your answer as 6.8

[floral trail]

ok

[alpine sable]

\times for the standard multiplication sign, or \cdot for the interpunct. \dfrac sets your fraction in display style, \tfrac displays your fraction in text style, \frac implies the previous. Each hyperbolic function, trigonometric ratio are specials chars (characters) so they'd have their very own syntax. Use {} for grouping stuff. In brackets use \left \right for autoscaling the bracket like

$\left(\dfrac{a}{b}\right)$

thnk youu screenshotin that thats really useful couldn't find anything online when i looked up a guide for texit

[ocean seal]

Several people are

[ionic jewel]

some other common ones: \int_{a}^{b} for integrals, _ for subscript

[alpine sable]

^ for superscripts

(I think we all know that)

yep lmao

[ionic jewel]

\sum_{i=0}^{j} for sum, \lim_{i \to \infty} for limits

cant think of other ones i use a lot here

\log \sin \cos...

[alpine sable]

\text for text

there are other syntaxes for text

Can't remember em

oh yh ik this one

, tex hello

[ocean seal]

sxkura

[vale wigeon]

\frac{num}{denom}

[mortal oracle]

are u guys using the channel

[ionic jewel]

no

ask away

[mortal oracle]

ok I have a triangle and im supposed to use the pythagoras theorem or sohcoatoa

how do i know which one to use or is it the same

[alpine sable]

They are both different

[ionic jewel]

who calls comp sci com science

[vale wigeon]

what do you need to find, h7mood

[alpine sable]

I do 🥲

[alpine sable]

Both used in Right Angled Triangles

[mortal oracle]

wait let me upload a picture

[vale wigeon]

pythagoras' theorem can give you a side if you know the other two sides

[alpine sable]

Pythagorean Theorem solves for side lengths

Your Trig Ratios solve for Angles and Sides

[vale wigeon]

why Capitalize Random Shit

[mortal oracle]

solve for the angle

[vale wigeon]

also what is up w/ that triangle

it looks mislabeled

[alpine sable]

very

[vale wigeon]

how can a leg and the hypotenuse be both 8.6 km

[ionic jewel]

• not drawn to scale

[vale wigeon]

that'd make the angle zero lmao

[alpine sable]

[mortal oracle]

oh wait

the teacher said there is a mistake

lol

[alpine sable]

It's what I do

[mortal oracle]

the hypotenuse is supposed to be 18.6 apparently

[ionic jewel]

oh i thought your math teacher could bend reality to their will to change the triangle

[vale wigeon]

oh so the hyoptenuse is 18.6km ok then thats fine

and you want the angle

presumably you have a calculator that can do inverse trig functions

[vale wigeon]

recall your SOH-CAH-TOA to see that you're given the adjacent side to theta and the hypotenuse

[mortal oracle]

this good now?

[vale wigeon]

yes you've now corrected it

anyway, once you do what i said, you get ||cos(θ) = 8.6/18.6||

[mortal oracle]

ok

do we then get cos(θ) * 18.6 = 8.6

[foggy knot]

Can someone tell me how to find exponential rate

oh im sorry I should have read the rules about this my b

[gray isle]

do we then get cos(θ) * 18.6 = 8.6
that's something you "could" do
but in no way helps you determine the value of θ

[mortal oracle]

ok how should I go about solving for theta

[gray isle]

inverse trig

[mortal oracle]

u mean cos^-1

[gray isle]

in this case yes

[regal pendant]

write an equation of the circle with center at the origin, containing (-6, -8). i'm sorry i just dont know how to start

[gray isle]

are you familiar with the center form of the equation of a circle?

[regal pendant]

sort of

(x – h)2 + (y – k)2 = r2 right?

[gray isle]

^ for exponents

[regal pendant]

yes

[gray isle]

do you know what the variables h,k,r represent?

[regal pendant]

h and k are center

[gray isle]

bad wording

[regal pendant]

idk about r

[gray isle]

(h,k) is the center of the circle

r represents the radius

[regal pendant]

ok, so it should be....

(x + 6)^2 + (y + 8)^2 = r^2?

[gray isle]

well r is something you need to determine

which you can do by applying the definition of the radius of a circle and distance formula

[vale wigeon]

also your circle isn't centered at (-6,-8). it goes through (-6,-8).

@regal pendant

[gray isle]

^

[regal pendant]

so what would that change exactly?

[gray isle]

the centre determines your values of h and k

[regal pendant]

so are h and k still -6 and -8

[gray isle]

no

reread what you question is saying

the circle is centred at what ?

[regal pendant]

i didnt know what origin was, thnx. but what would -6 and -8 be?

[vale wigeon]

(-6,-8) is a point on your circle

[gray isle]

i didnt know what origin was
maybe you should mentioned that earlier,
the origin the point with coordinates (0,0)

[vale wigeon]

also you should know what a circle is, geometrically

[regal pendant]

yes sorry, my mind is kinda fried rn. ( no not drugs)

[vale wigeon]

can you recall the definition of a circle?

no equations. just the pure geometric definition.

[regal pendant]

a shape with a center and radius that is constant from it?

[vale wigeon]

that's.

bad wording

a circle is a shape consisting of all points which are at a fixed distance [the radius] from a fixed point [the center]

[regal pendant]

OK

[vale wigeon]

the radius of a circle is the distance between its center and any of the points on it

so now, given that you know your circle's center is at (0,0)

and one of the points on the circle is (-6,-8)

what is your circle's radius?

[regal pendant]

10?

[vale wigeon]

why the question mark?

are you uncertain about your answer?

[regal pendant]

I mean yeah, im not the smartest but im trying

[vale wigeon]

okay, tell me how you worked out your answer and where you're beginning to doubt yourself.

[regal pendant]

I used the distance formula and replaced -6 and -8 for for the first x and y

[vale wigeon]

you used the distance formula to find the distance between which two points?

[regal pendant]

(-6 - 0)^2 + (8 - 0) ^2

Yes

[vale wigeon]

this wasn't a yes/no question

so you used the distance formula to find the distance between (-6, -8) and (0,0), it looks like.

if that's the case, then you did exactly what you're supposed to.

[regal pendant]

so my equation should look like this(-6 - 0)^2 + (-8 - 0)^2 = 10^2

[vale wigeon]

this is not the equation of your circle, this is just an equation detailing your arithmetic.

[regal pendant]

ok, what do i need to do to change it?

I mean it seems like I have the equation for the circle do I not?

[gray isle]

the equation of a circle with centre $(h,k)$ and radius of length $r$ is given by:
$$(x-h)^2+(y-k)^2 = r^2$$

[ocean seal]

ℝamonov

[regal pendant]

is it not just $$(-6-0)^2+(-8-0)^2 = 10^2$$

[ocean seal]

Syplix

[regal pendant]

or do i need to work that out?

but there would be no way too, nvm

[gray isle]

the equation of a circle is supposed to give you a relation between x and y
the equation you just typed although true doesn't do any of that

for the equation as outlined above, you only needed to know/use the coordinates of the centre and the radius

[regal pendant]

ok

[craggy bronze]

can someone help me simplify this?

basically i need a factor of $(1-4x²)/x²$ one of which is $x - ½$

[vale wigeon]

did you miss some parentheses?

[craggy bronze]

$(1-4x²)/x²$ one of which is $x - (1/2)$

[vale wigeon]

did you really mean to divide by x and then subtract 1/2

[ocean seal]

slmnsknrll

[vale wigeon]

or did you mean $\frac{1-4x^2}{x^2} \big/ (x - \frac{1}{2})$

[craggy bronze]

sorry. x-½ should be inside a parentheses

[ocean seal]

Ann

[craggy bronze]

yup that's it

[vale wigeon]

anyway you know you can just multiply by 1/(x - 1/2) instead you know

or by 2/(2x-1) which is the same thing but without the nested fractions

[craggy bronze]

hmm I'm not sure i understand what you mean but I'll try

[vale wigeon]

$\frac{1-4x^2}{x^2} \big/ (x - \frac{1}{2}) = \frac{1-4x^2}{x^2} \cdot \frac{1}{x - \frac{1}{2}} = \frac{1-4x^2}{x^2} \cdot \frac{2}{2x-1}$

[ocean seal]

Ann

[craggy bronze]

oh i understand now

[vale wigeon]

this is what i mean

[craggy bronze]

hmm okay wait I'll check

how was the 2/2x-1 at the end derived?

[vale wigeon]

parentheses!!!!!!

it's 2/(2x-1).

[craggy bronze]

ohh

[vale wigeon]

but to answer your question,

[craggy bronze]

sorey

[vale wigeon]

i multiplied the num and denom in 1/(x - 1/2) by two

[fleet stream]

Is this occupied

[craggy bronze]

no

[fleet stream]

Can someone help me with this, I cant isolate the Y because nothing seems divisibe by the two equations, I tried 7x-21y=54 but 54 cant be divided by 7

[vale wigeon]

i mean

fractions exist

[alpine sable]

are you allowed to use rational numbers?

[fleet stream]

I guess so

[vale wigeon]

i mean you can also do elimination instead?

[fleet stream]

It need to be done in substitution

[vale wigeon]

oh so there's an explicit instruction to do that

ok

is there also an explicit instruction to not use fractions at any point?

[fleet stream]

No

[vale wigeon]

great

so you were going to isolate y

why not do that in one of the equations

say, the first one

you'll get y = (5x+35)/4

[fleet stream]

Oh it'll be in fraction

[fleet stream]

And this is what ill input in the second equation?

[alpine sable]

I'm in a bit of a pickle related to vectors and I genuinely dont have the faintest clue on how to do it, can someone help me?

[vale wigeon]

what kind of pickle

[fleet stream]

Is it going to be like this? @vale wigeon

[vale wigeon]

no

also uh @alpine sable youll need to move to another channel

@fleet stream you should put (5x+35)/4 where y is. not just at a random point within the equation

[fleet stream]

Oh I misplaced it

After the 21 right

[native temple]

how to solve a system of 3 equations when 2 variables cancel

i.e you solve for X and you get 2X = 12

and 2 other equations

with 3 variables?

I get stick on this

and no tutorial adresses this.......

[vale wigeon]

wym "two variables cancel"

im not sure what you mean by this. is there a system you're looking at?

[native temple]

not right now

I forgot an example

but one a system when yoi do elimination 2 varibales cancel

[vale wigeon]

so what you're saying is that you found the value of one of your variables?

then what's the issue? just plug it in everywhere and now you have a system of two variables only!

[native temple]

5x + 5b + 5c = -30
4x + 3b + 3c = -6
-4a + 3b + 3c = 9

for example

these cancel each other

and when I add diffrent equations]

X is a diffrent result

[vale wigeon]

nyeh?

this looks like four variables

x, a, b and c

[native temple]

cc???

wait c isn't a variable

it's a constant

[vale wigeon]

bruh

[native temple]

and that's Y

[vale wigeon]

okay so like

mega bruh moment

[native temple]

is 2 a variable?

[vale wigeon]

i asked

is there a system you're looking at?
and you said no

and then you give me a system

which you could've given me at the start

[native temple]

ummmm

[vale wigeon]

no 2 isn't a variable

...

i have to go now i guess

class

[native temple]

noooo

also why didin't I learn this

how to solve this system? #help-0 message

5a + 5b + 5c = -30
4a + 3b + 3c = -6
-4a + 3b + 3c = 9

<@&286206848099549185>

[alpine sable]

gauss elimination is a way

[native temple]

???

gauss what?

the way I learned was

subtitute and elimiate a system

And for matrixes I learned ti-84

that's it

[alpine sable]

x+b+c = -6
so ,
3x+3b+3c = -18
and
4x+3b+3c = -6

. So , x=-12
So , b+c = 6

And -4a+3b+3c=9
So , a = (9-18)/-4 = 9/4 = 2.25

[native temple]

wait what??

[alpine sable]

?

[native temple]

X = a

[alpine sable]

how

[native temple]

missnaming

that's how

[alpine sable]

5x + 5b + 5c = -30
4x + 3b + 3c = -6
-4a + 3b + 3c = 9

you wrote this

[native temple]

yes because the problem of my kuta sheet was

5a + 5b + 5c = -20
4a + 3b + 3c = -6
-4a + 3b + 3c = 9

and when i add equations 2 and 3 together

3b and 3c cancel

leading to 8a = 15

*-15

and IDK what to do

[alpine sable]

wait adding eqn. 2,3 doesnt cancel 3b,3c .. it cancels 4a

.. if you subtract them. then 3b , 3c cancel

[native temple]

2 and 3 * -1

yes subtracting them

so now what or should I go back

and just add them?

IDK what to do

help

[alpine sable]

these equations cant exist simultaneously

[native temple]

so add 2 and 3?

[alpine sable]

if you solve 1,2 .. you will get a = -6 .. if you solve 2,3 .. you will get a = -15/8
and if you solve 1,3 . you will get a =-3

[native temple]

oh

is that for A?

[alpine sable]

yes variable a

[native temple]

I know it's confusing when solving for A

so why is A diffrent is there no solution?

[alpine sable]

yeah thats why these all equations cant exists simultaneously

[native temple]

ohhhhhhh

[alpine sable]

there is something wrong maybe ig

[native temple]

that's why it's confusing

isthat a solution

this

[silent pewter]

how do i solve for this?

[exotic quiver]

14-7+3-14 is it 18 or -4

my friend noob he thiks it -4

<@&286206848099549185>

[solemn juniper]

It is -4

[jade birch]

,w 14-7+3-14

[ocean seal]

Results provided by WolframAlpha

Click here to refine your query online
Upgrade to WolframAlpha Pro!

Requested by .itsjustnai#9187

[jade birch]

@Arin#5896

He's gone xd

[solemn juniper]

Ok bye ig

[jade birch]

[north hemlock]

It seems he was the noob 😔

[hardy geyser]

<@&286206848099549185> anyone on at this time?

[jade birch]

At what time? It's 10am here

[hardy geyser]

4 am

[jade birch]

Then no

[gray isle]

don't ping helpers immediately. especially not before asking a math quesrion

[hardy geyser]

The wording is confusing me?

[gray isle]

#❓how-to-get-help

[hardy geyser]

or is it just me?

Sorry

[alpine sable]

(x/100) * 86 = 18 ..

solve for x

[north hemlock]

How much of 86 does 18 make up as a percent

If that wording makes more sense

[hardy geyser]

I did 86 x 18 / 100

[alpine sable]

it will be (18/86)*100

[jade birch]

And as you can see, you didn't need Helpers for this

[hardy geyser]

Wait 18/86?

[gray isle]

pay close attention to the position of the of and is

[hardy geyser]

Not multiply ?

[alpine sable]

why are you learning , that whether it will be multiplied or divided .. just remember what percentage means and how to write expression for it.. you can found any unknown from that

[hardy geyser]

what percentage OF 86 is 18

so like what is 86 percent of 18? did i say that right?

[gray isle]

no

[hardy geyser]

ughhh brain hurts ok so when they say what there asking for the x of 86?

[gray isle]

like you said, OF is multiply.
(IS will be equal)

what percentage * 86 = 18

[hardy geyser]

ok ok 86=18

[gray isle]

no

86=18 is nonsense

[hardy geyser]

wait I think I understand we’re trying to find what percentage of 86 would make 18 yes?

[gray isle]

yes...

[hardy geyser]

OHHHH

[gray isle]

I mean that's exactly what the question says

[hardy geyser]

x/100*86=18?

[gray isle]

yes. that would be an appropriate equation.

[hardy geyser]

@gray isle did I do this correctly sensei

[gray isle]

,calc 18/86

[ocean seal]

Result:

0.2093023255814

[gray isle]

looks ok

[hardy geyser]

wait all you had to do was 18/86?

what so the equation thing was uncensored

uncesseryryy

[gray isle]

well multiply by 100% to get the percentage

[hardy geyser]

uncessery

[gray isle]

the equation clearly tells you and any reader what you're doing

if you don't set the proper equation to represent your problem, you may end up getting something different or irrelevant

[hardy geyser]

ok so don’t do what you did?

[gray isle]

I prompted that command to do a quick check

the equation and work leads to
x = 1800/86 %

[hardy geyser]

ok thank you sensei

[gray isle]

which you would then enter into a calc to get your percentage and answer

[maiden badge]

can som1 help me with this? I cant understand

[vale wigeon]

what even are these?

[maiden badge]

numbers

[vale wigeon]

oh i see the first line now

[maiden badge]

Directions: Calculate the percent increase or decrease between the starting and ending quantities
below. Round your answer to one decimal place.

[vale wigeon]

it's half cut off

yeah those

okay

do you know how to calculate percentage increases and decreases?

[maiden badge]

no

[vale wigeon]

do you know what percentages are, in general?

[maiden badge]

yes

[vale wigeon]

okay

do you want me to take you through one of these examples, and if so, which one?

[maiden badge]

5th pls

[vale wigeon]

ok

you have a value that used to be 30 and now went up to 60

what is the absolute (i.e. not percentage) change?

[maiden badge]

yes

idk

uh

[vale wigeon]

you had $30 yesterday and now you have $60. how much money did you gain or lose?

[ocean seal]

Ann

[maiden badge]

i gained 30

$

[vale wigeon]

great

so the absolute change is +30

[maiden badge]

yea

[vale wigeon]

what percentage of the old value (30) is that?

[maiden badge]

50% ?

[vale wigeon]

30 is 50% of 30?

no, that's incorrect.

[maiden badge]

oh ok

100%

[vale wigeon]

there we go

[maiden badge]

yay

so is the answer 100%?

[vale wigeon]

yes

the answer is 100% increase

[maiden badge]

yay thx

[gray isle]

_{use these braces if your subscript contains more than one character}

$f_{xx}$

[ocean seal]

ℝamonov

[fast jay]

A roulette gives red (R) and black (B) each with the probability 1/2 and different rounds are independent of eachother. Determine the expected amount of rounds until the sequence (R,R) occurs. Not sure how to go about this problem, any advice?

[vale wigeon]

i wanna say markov chains?

gimme a moment

[fast jay]

Haven't started doing that yet. I got a lead that let X be the amount of rounds in total. Xr respective Xb be the amount of remaining rounds if the last round was R respective B.

Somehow using expected value

I thought. E(X) = 1 + E(Xr)

1 since we always have the first round and I add E(xr) since thats the amount of remaining rounds until we get red again if previous one was red I guess but that was not correct

[vale wigeon]

im getting some bullshit results, and i'm almost certain my reasoning falls short somewhere but i can figure out where.

[fast jay]

The answer is 6 if that helps

[vale wigeon]

i'm getting that the expected number of turns unti seeing RR is 6 when startring from RB or BB, and 4 when starting from BR

wait hold on

hm.

ah no i do get 6

one moment.

[fast jay]

Thanks for your time, I appreciate the help

[vale wigeon]

ok so this is kind of a markov chain but im not gonna call it that so as not to scare off the hypothetical grader

every round you can imagine starting at one of these nodes and following one of the arrows going out of it with probability 1/2

[fast jay]

Yeah I follow your drawing and what that means

[vale wigeon]

okay

so let's look at node BR

a is the expected number of rounds until RR

but let's compute it differently

first, we get the 1 round that we'll have no matter what. since we're not at RR yet we are spinning the wheel.

then, we either get into RR (probability 1/2) - which gives us 0 rounds until RR - or we get into RB, which gives us b rounds until RR

thus $a = 1 + \frac12(0) + \frac12 b$

[ocean seal]

Ann

[vale wigeon]

does that make sense?

i'm going to set up two more equations like this shortly

[fast jay]

Yes

[vale wigeon]

okay

similar logic gives $b = 1 + \frac12 a + \frac12c$ and $c = 1 + \frac12 c + \frac12 a$

[ocean seal]

Ann

[fast jay]

One sec

Okey yeah I follow so basically this is similar to conditional probability/expressed in a different way, yes?

[vale wigeon]

kinda?

more conditional expectation than conditional probability

[fast jay]

Well this is not probability

yeah

[vale wigeon]

but yeah it's basically that.

in any case, this is a system of three linear equations in three unknowns, which i hope is not hard to solve

[maiden badge]

Directions: Calculate the percent increase or decrease between the starting and ending quantities
below. Round your answer to one decimal place.

Start: 9
End: 20

Ermmm i need help with this 1

[fast jay]

Alright thank you for the help, I understand the approach. Once again I appreciate it!

[vale wigeon]

@maiden badge you're gonna need to wait or move

[maiden badge]

oki

[vale wigeon]

oh, eddyy is done now i guess

[maiden badge]

ill wait

[vale wigeon]

@fast jay do you need me to continue or can you take it from here?

[fast jay]

I think I'll manage, I'll try on my own and come back if I stumble upon any issues. Thanks!

[vale wigeon]

k

[vale wigeon]

follow the same principle as the previous one we had

absolute change = new - old

percentage change = 100% * (absolute change)/old

[maiden badge]

okay

11

[vale wigeon]

11 what

11 monkeys?

[maiden badge]

absolute value

[vale wigeon]

absolute change

[maiden badge]

change*

[vale wigeon]

the absolute change is 11 yes

[maiden badge]

yes

100% x 11?

[vale wigeon]

no

i encourage you to read my messages carefully

[maiden badge]

okay

[vale wigeon]

i don't appreciate it very much when parts of the messages i send get flat out ignored

[maiden badge]

alr

11/9?

[vale wigeon]

yes divide 11 by 9

and then express as a percentage

[maiden badge]

oki

[rancid dirge]

Hello, I have an exercise that I do not understand. maybe someone can help.

[maiden badge]

its french!

[rancid dirge]

I know 😭

I'll try to translate

[polar anvil]

wat is 1 + 1

[rancid dirge]

6.5 % of the swiss population have corona. PCR test is 90 % right

[main apex]

3

[rancid dirge]

That means when a person is infected, the test will be positive in 90% of the cases.

[gray gorge]

Sounds like a Bayes theorem question to me

[rancid dirge]

The false rate is 5 % ( this means the test will be positive, but the person is healthy)

[jagged imp]

thats probably what la formula de bayes is

[rancid dirge]

it is

right now I have P(P | I ) = 0.9, P(P | S)=0.05

and that 6.5 % of the population is infected

how would i calculate P( I )

[gray gorge]

Isn't that just the 6.5%

[rancid dirge]

first question: we take a person randomly from the population, what is the probability that he is infected? what is the prob that he is healthy?

[rancid dirge]

is it that easy?

[gray gorge]

It's what the question prescribes, no? 6.5% of the population is infected

Regardless of what test results say

[rancid dirge]

ok

[gray gorge]

First sentence of the exercise

[rancid dirge]

I think I will come back later to this exercise and solve another one right now

thanks for the help

[gray gorge]

np

[rancid dirge]

you actually helped a lot

i could solve this exercise

sometimes i tend to overthink things

[rancid dirge]

I have another question

We throw a dice two times and have following events:

A1: at first throw there is an even face number

A2: at second throw, there is an even face nnumber

A3: the sum of both presented face numbers is an even number

I need to prove that A1 and A3 is pair wise independent

A1 and A2 is pair wise independent

A2 and A3 is pair wise independent

I also need to prove that the events A1,A2,A3 are dependent

Any ideas?

[vale wigeon]

dfgkljdfklgsjdflkhdjskfglslkgljk

the title of the section is in french

but the section itself is in german?!?!?

😂

[quick surge]

how can i find x

i just need to know how i can find x

[alpine sable]

ask in an unoccupied channel, i can help you there

[quick surge]

oh sorry

[rancid dirge]

yeah, education in Switzerland 😫

I could solve the exercise, this channel is unoccupied

[nimble matrix]

ok

sorry

[rancid dirge]

no it's ok you can ask your question

[vale wigeon]

?

[fast jay]

Sec

Accidentally posted in advance

[fast jay]

I solved it by doing this and then taking 1+1/2a+1/2b=6, did you have anything else in mind? Since 1 is the first round we'll have no matter what and then I thought that 1/2a = rounds until 2 red if most recent was red and 1/2b = rounds until 2 red if most recent was black. Thus c is only used in the system of equations

[vale wigeon]

?

not sure i follow.

in my solution, the expected number of turns from start to RR is 2 + (0+4+6+6)/4, to account for the two starting rounds and the fact that all four nodes are equally likely to land into.

[fast jay]

Oh I see, but was my approach just a coincidence or does that also work?

I solved the system of eqns giving me (a,b,c)=(4,6,6). And then to get the expected amount of rounds until 2 red I took 1+1/2a+1/2b which is 1(first round), 1/2a(rounds until 2 red given that most recent one was red which we see is 4), 1/2b(rounds until 2 red given that most recent one was black which we see is 6).

Instead of 1/2b it could've been 1/2c as well since in both those cases the most recent one is black. Sorry for bad formating but by 1/2a I mean a/2 etc

[vale wigeon]

wlel

well*

i guess this logic kinda works?

[bleak nymph]

S=a⋅b/2
How would the formula look if I wanted to calculate a?

[vale wigeon]

calculate a knowing everything else?

multiply both sides by 2 to get 2S = ab, then divide both sides by b to get a = 2S/b

[bleak nymph]

I meant like, how would it look if it were a formula

a=...

Is it a=S/2b?

[vale wigeon]

no? why would it be that

[bleak nymph]

ya, i don't know. That's what I'm trying to figure out

[jade birch]

this is how you figure it out

[vale wigeon]

i just described to you in full detail how to figure it out

[bleak nymph]

nvm

I read it wrong

English isn't my first language, sorry about that

[drifting phoenix]

Could anyone help me with this question?

[spare fern]

Writing numerator and denominator in polar forms looks like a good place to start

[patent plinth]

you could just multiply the numerator and denominator inside the bracket by (1+i)

[drifting phoenix]

They haven’t given a sum for i. So it’s impossible to be solved right?

[noble sinew]

Try to write down the first few terms then you will notice it can be solved

[patent plinth]

yeah! also its better if you simply the term in the brackets first

[kind verge]

i think i got x for this, but Im not sure

its for a review assignment

(x-10)(x+6)

(x+6)(x+6)

cancels out and gets x i think

[patent plinth]

yep! you're correct. @kind verge

everything cancels out after factorising except x

[kind verge]

alrighty 👍

for this one so far i've got

(x)
------ - (x+8)(x-2)
(x+8)(x-2)

not sure what to do afterwards

[patent plinth]

yeah so you're getting this, right?

$\frac{x}{(x+8)(x-2)} - \frac{5}{x+8}$

[ocean seal]

Solitary

[kind verge]

yep

[patent plinth]

so you can factor out the 1/(x+8), right?

[kind verge]

yea, i think

wait, would get you something like this

• 2(2x-5)/(x+8)(x-2)

[patent plinth]

$\frac{1}{x+8}[\frac{x}{x-2} - 5]$

[ocean seal]

Solitary

[patent plinth]

like this i think

[kind verge]

kinda confused

i got somehting like this

[patent plinth]

no no. we factored out the 1/(x+8)

umm, got this?

[kind verge]

so we would just cancel out the (x+8)

[patent plinth]

yeah. so it becomes like this

[vale kayak]

this is still correct

[kind verge]

[patent plinth]

haha tru. but i'm going some other way

[kind verge]

oh, yea, its only one fraction as well

[patent plinth]

you would get this as the final answer

[patent plinth]

this

[kind verge]

k thanks everyone

[keen zephyr]

How would I do part b

I have no idea how to get started either

[full gale]

Try drawing a line on your graph which is parallel to the x axis and intersects your circle

And then draw a triangle inside your circle which has vertices at the centre and at the two points where the line intersects the circle

And think about what the equation of the line might be from that

Given that you know the lengths of the edges of the triangle

[keen zephyr]

like this?

[full gale]

Uh one point going through the centre of the circle

And the other 2 points of the triangle going through the points where the line intersects the circle

[keen zephyr]

Oh do you mean this?

[full gale]

Yeah

[keen zephyr]

Now I know radius of them to be 6

[full gale]

And then the ‘height’ of the triangle will be related to the equation of the line

Bc the equation for the line will be y = (y centre of circle) +_ height of the triangle

[keen zephyr]

Ah ok I think I can figure out the rest thank you!

[full gale]

Np

[jovial knoll]

The amount A of money that accumulates in n years if one dollar is invested
and if the interest is compounded annually at the fixed rate of i per cent per
year is A = (1 + i)^n. As the formula is written, which is the independent
variable? Which is the dependent variable?

this is a very simple question

[full gale]

Often look for triangles and stuff when it comes to geometry questions like that

[jovial knoll]

would the independent variable be n (time) and the dependent variable would be A (total money)? sorry i know this but i just want to know what would i be?

would i also be considered a dependent variable?

[alpine sable]

is c correct?

[golden arch]

Find the straight line parallel with alpha1 : x +2y +4z = 8 and Alpha 2: x - y - 2z = 6 and trough p(2,1,0)

This is my solution, is it correct?

[elfin hazel]

yes

[alpine sable]

ty

@elfin hazel

may i dm u?

[elfin hazel]

sure, but why not just say here lol

Technically yes (if u plot a graph, it'd likely be total money against years

[elfin hazel]

depends on the question, basic qns would treat "i as a constant" but technically it's not wrong to plot a 3d graph of all 3 variables

[wheat turtle]

Can someone help

[tight locust]

it's just the absolute difference

this is first grade math

[daring chasm]

well maybe not first grade because decimal numbers scary

but yeah, just take 16.1 - 15.7

[drifting edge]

I need help with this one

[fading zephyr]

oi

this is a quiz

[spare fern]

If you need help with quizzes then ping mods

They handle such questions

[drifting edge]

oh

ok

[wheat turtle]

help pls

[obsidian crane]

c = 5q

whats difficult ?

@wheat turtle

[wheat turtle]

thats my freinds quiz @obsidian crane

[pearl wraith]

bruh

[alpine sable]

Heyo

I need help with these 3

[obsidian crane]

b = 3t + 13
c = 2t + 6

(a + b + c)/3

( (t + 5) + (3t + 13) + (2t + 6) ) / 3

(6t + 24) / 3

2t + 8

For 14 :

[willow bluff]

Hello does anyone know how to do this without using sin and trig

[obsidian crane]

form the equation using the statement : a = b + 5

multiply 5 on both sides

isolate 5b

[pearl wraith]

use sin

[willow bluff]

Mainly working with Pythagorean theorem and special rights

Can’t use sin haven’t been taught it

[pearl wraith]

ill teach you it

[alpine sable]

can i see your work for 14 and 15? lol

[pearl wraith]

so sin is o/h

opposite over hypotenuse

[alpine sable]

U can dm me if u feel like

[obsidian crane]

a = b + 5
5a = 5b + 25
5b = 5a - 25
5b = 5(a - 5)

[pearl wraith]

and so sin 60° = 15/h

now isolate h

and you have your answer

for x

[obsidian crane]

@alpine sable for 15 just slove for y

You know how to do that ?

[alpine sable]

so, 14 is a?

[obsidian crane]

yes

[alpine sable]

is it D?

[obsidian crane]

c

[alpine sable]

I see

how'd u get your answer?

@obsidian crane

[obsidian crane]

solve for y

[vale wigeon]

@obsidian crane don't just give out answers please

[obsidian crane]

ok

[obsidian crane]

multiply (y - 2x) on both sides

you should know how to do that 0.0

[alpine sable]

hmm

[vale wigeon]

@tight locust why the sully

[alpine sable]

@obsidian crane

https://youtu.be/j0TUZdBmr6Q

[obsidian crane]

hmm many things can represent a linear equation

like the cost of taxi per km

that will be a very simple one

forexample if a taxi takes 5$ per km , 'x' being the distance in km and 'y' being the total cost then the equation will be y = 5x but it's too simple

[indigo bramble]

i have a stupid question

-log(a/b) = log(b/a) is this correct

[alpine sable]

• (log(a) - log(b)) = log(b) - log(a)

[indigo bramble]

ty

[alpine sable]

log(b) - log(a) = log(b) - log(a)

[tidal oyster]

help?https://media.discordapp.net/attachments/827298017526808637/828820300242092042/unknown.png?width=717&height=321

[rapid dock]

I need quick help

Like rn

[tidal oyster]

help pls

[rapid dock]

I need to find the pentagon

So

I got the triangle which is a part of the pentagon, its bh/2 = 6

How do i get the quadrilateral in the pentagon now?

[tame shell]

needing help quickly sounds like a test

[rapid dock]

its an assignment due at 11

Could u help?

[tame shell]

i dont like helping people on a time constraint

[rapid dock]

Itll be quick

[tough tangle]

lol

[tame shell]

why should your stress be my stress

[rapid dock]

Its cuz i have class in 2 min

But its fine

Does anyone know?

[tough tangle]

split it up into triangles

a^2 + b^2 = c^2 so you can find the diameter of the circle

also quadrilateral edc<diameter> is a cyclic quadrilateral

so opposite corners have angles that total to 180\

triangle ab<diameter> has area 1/2 * 3* 4

so 6

[rapid dock]

Diameter = 5

Triangle left = 6

And the quadrilateral on the right?

[tough tangle]

split quadrilateral into 2 triangles

you should be able to do it on your own now

area of triangle formula = 1/2 * ab sin(C)

where C is the angle between sides a and b

goto another channel

[frank nacelle]

sorry

[tough tangle]

@rapid dock sooo

were you able to do it?

[rapid dock]

Nope still trying

Confused in Spanish class lol

[tough tangle]

im not sure exactly how much of trigonometry you know but i was able to find an answer out

so it is technically possible to solve it

[rapid dock]

Damn

[alpine sable]

The area of ​​a triangle can be calculated with the formula A = G * h / 2
Which of the five terms is a correct paraphrase of the formula?

[rapid dock]

So how do i get it

[tough tangle]

ok so

first you have to find the length of the red line

[rapid dock]

Then?

[tough tangle]

then, 2) find area of two triangles immediately by using heron's area formula

or 2) find red colored angles and use area = 1/2 ab sinC to find area

[rapid dock]

What the red line?

[tough tangle]

i sent a picture

are you seeing it

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