#help-0

1 messages · Page 108 of 1

limpid turret
#

Gotcha

#

And is y, the cooldown reduction, measured in seconds or percentage?

next tundra
#

Seconds

limpid turret
#

Okay

prime badge
#

that's what google says the formula is for yasuo

#

but that's from bonus

#

oh it's year old info

next tundra
#

The guy I'm trying to solve this for said this

#

❤️ — Today at 2:30 PM
yea that is what i need
The problem with this is you have to account for the asymptote or restriction at y = 4 while also account for the infinite plateau of y cd at some >= x value
my idea was a negative logistic growth equation
which is just a inverse
equation

#

Idk what it means

limpid turret
#

Sounds like nonsense tbh

#

Think they're just trying really hard to sound smart

prime badge
#

the point is it doesn't automatically go horizontal after the cap

#

they want to solve that

#

i don't know what they want to happen on the left side

#

it's not hard to do the zigzag with abs

next tundra
#

Ok

#

Thanks for the help

prime badge
#

it goes flat on both sides automatically

#

@next tundra

lone heartBOT
#

@next tundra Has your question been resolved?

#
Channel closed

Closed by @next tundra

Use .reopen if this was a mistake.

lone heartBOT
#
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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

craggy hill
#

Hello, I posted earlier today my question but I am not sure I understand. Basically I need to calculate Pokemon attack/damage/hp. My math was 44 - ((55/2) * 65/100) = 26.125 but apperently it is not correct. I was pointed out that I should 100-65 and that makes 44 - ((55/2) * 35/100) = 34.375. But I don't udnerstand, what if Pokemon has defense over 100, I will get negative result? Please help me formulate formula for this example. HELP

lone heartBOT
#

@craggy hill Has your question been resolved?

lone heartBOT
#

@craggy hill Has your question been resolved?

lone heartBOT
#

@craggy hill Has your question been resolved?

alpine sable
#

In this case, the formula should be quite clear. First, let's label the variables (you can use different labels for your purposes of course):
a is the attack strength of the attacking pokemon
d is the defense of the attacked pokemon
h is the current HP of the attacked pokemon

First, since the attack strength is lowered by half, we have a/2. Next, a certain percentage of this will be blocked. Here we're only interested in the percentage of the damage that isn't blocked, which is 1-d/100. Multiplying these 2, we get the actual damage dealt, which is a(1-d/100). Then, subtracting that from the current HP, we get h-a(1-d/100) as the new HP

craggy hill
alpine sable
craggy hill
#

.close

lone heartBOT
#
Channel closed

Closed by @craggy hill

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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

real rune
lone heartBOT
real rune
#

i have the answer already

#

but

#

i wanted to ask something about the domain

#

so basically

#

thats my work and i was wondering how the forced domain change works

#

like if the domain is already at -pi <= 2x <= pi

gilded vessel
#

,rotate

ocean sealBOT
real rune
#

do i have to double the domain again?

gilded vessel
#

double the domain?

real rune
#

well like you know hjow normally it would be like

#

-pi <= x <= pi

#

like the x is just x

#

if its already given as 2x

#

-pi <= 2x <= pi

#

do i have to double it since my angle is a 2x angle

#

or does the 2x in the given domain already fulfill that requirement

#

like the forced domain change thing

gilded vessel
#

i dont understand what you are asking

#

theres nothing to double

#

having the domain for 2x works well since thats the input of the trig function

#

you know there is another solution for tan every multiple of pi

real rune
#

yeah sorry if its a little confusing

gilded vessel
#

but that will exceed the domain

real rune
#

yea

#

but

#

ok so for double angles

#

the domain must fit for the double angle right?

#

so like normally it would be like

#

-2pi <= x <= 2pi

#

right

gilded vessel
#

i think you are confused because the domain is usually given in terms of x

#

lets say the domain for this question was

#

0 <= x <= pi

real rune
#

ya

gilded vessel
#

this is just an inequality

#

you can multiply it all by two

#

0 <= 2x <= 2pi

#

then you will have another solution

#

its useful to have a domain for the body of the trig function

real rune
#

but if the angle im finding is a double angle

#

doesnt the domain have to be doubled?

#

like can you do tan2x = -1

#

in the

gilded vessel
#

double angle isnt some special angle

#

its just a word

real rune
#

-pi <= x <= pi

ornate condor
#

fancy~

gilded vessel
real rune
#

here

#

lemme send a picture of notes i took

#

the forces domain change thing

gilded vessel
#

they really did nothing special

#

they just multiplied the inequality by 2

#

the point of that is just to have the domain in terms of the input of the trig function

#

thats all

#

the "forces domain change" is just confusing

real rune
#

when would i multiply and when would i not

#

cus like

#

if i multiply the number of answers would change

gilded vessel
gilded vessel
#

its only for convenience

real rune
#

wait really?

#

interesting

gilded vessel
#

as long as you multiply all parts you will get the same inequality in essence

#

yes for example

real rune
#

mmmm

gilded vessel
real rune
#

so the only important part would be

gilded vessel
#

lets say you multiply by 2

#

0 <= 4x <= 2pi

real rune
#

ya

gilded vessel
#

then lets say you get two solutions for 2x

#

2x = pi/4, 5pi/4

#

if you were to multiply both sides by 2

#

4x = pi/2 , 5pi/2

#

that first solution is still valid

#

but the second solution exceeds that domain

#

you can multiply as much as you want but the solutions stay the same

#

its just for convenience to have 2x in the middle

real rune
#

wait wdym the second one exceeds it

gilded vessel
#

so you know how many solutions to extract when you remove the trig function

real rune
#

5pi/4 is less than 2 pi

gilded vessel
gilded vessel
real rune
#

oh that one

#

mbmb

gilded vessel
#

since you multiplied both sides by 2

#

to get 4x

real rune
#

so in that case

#

when i did my answer

gilded vessel
#

you only multiply to have the domain in terms of the input

real rune
#

i got tan 2x = - 1

gilded vessel
#

its all for convenience

real rune
#

so if the domain given was say 0 <= x <= pi

#

i would not have to multiply

gilded vessel
#

wasnt it tan 2x = 1

real rune
#

oh yea mb

#

1

#

not -1

gilded vessel
#

its just

real rune
#

if u want to

#

?

gilded vessel
#

easier to have 2x in the middle

real rune
#

mmm okay

gilded vessel
#

since thats the input

#

and we get the number of solutions

#

when we apply the inverse

real rune
#

so then when i apply inverse i get pi/4

gilded vessel
#

its just easier to see how many solutions we should get at that poi nt

real rune
#

but since its tan 2x i would have to divide by 2 to get x

gilded vessel
#

yeah

real rune
#

ah

gilded vessel
#

you could keep the inequaliyty as is

#

0 <= x <= pi

#

its just

#

its not as easy to tell

real rune
#

so the domain multiplication is purely based off comfort

gilded vessel
#

how many solutions you get

real rune
#

ahhhhh okay

gilded vessel
#

another method you could do

#

tan(2x) = 1

#

then 2x = pi/4+ pi*k

#

where k is some integer

#

then solve for x

#

x =pi/8 + pi/2 * k

#

oops

real rune
#

wait so i have a question then

gilded vessel
#

i pmesse dp

real rune
#

if the solution i got was pi/4

#

cus technically tan 1 is just root2/root 2

#

but isnt tan also positive in quadrant 3?

gilded vessel
real rune
#

so would there be another solution?

gilded vessel
#

thats why a solution is every pi multiple

#

that would be quad 3

#

but its out of the domain

real rune
#

rn the only solution ihave is pi/8

gilded vessel
#

quad 3 is out of domain

real rune
#

oh yeahhh

#

ur right

#

because its 0 <= x <= pi

gilded vessel
real rune
#

i see

gilded vessel
#

we hae k =0

#

for x = pi/8

#

then k = 1

#

x = 5pi/8

#

then k = 2

#

x = 9pi/8

#

but then that third solution

#

exceeds domain

#

so you dont include that and stop there

real rune
#

wait

real rune
gilded vessel
real rune
#

lke the pi*k

gilded vessel
#

0 <= x <= pi

gilded vessel
real rune
#

what do u put for pi

gilded vessel
#

solutions to tan

#

are every multiple of pi

#

k is just any integer

real rune
gilded vessel
#

thats just a method u can do to not change the doman

real rune
#

oh wait nvm im dumb

#

mb

#

i see

gilded vessel
#

but its a lot easier for people to just do

#

0 <= x <= pi --> 0 <= 2x <= 2pi

#

then at this step

#

tan(2x) = 1

#

2x = pi/4, 5pi/4

#

adding pi again will be out of the domain

real rune
#

so the solutions would be pi/4 and 5pi/4?

gilded vessel
#

so its just for convenience to see how many solutions to extract at that step

real rune
#

for htat new domain

gilded vessel
real rune
#

ye

gilded vessel
real rune
#

well the updated one

gilded vessel
#

but those are the solutions for 2x

real rune
#

i see

gilded vessel
#

and the domain is in terms of that

real rune
#

okay so

gilded vessel
#

yeah so you dont need to worry

#

about multiplying the domain

real rune
#

what happens if

gilded vessel
#

and certain times

real rune
#

i have 2 factors

gilded vessel
#

its all just for convenience

real rune
#

one thats cos3x and one thats sin2x

real rune
#

like for the domain i just use original domain and multiply accordingly

#

depending on the x right

gilded vessel
#

yeah

real rune
#

ah okay

gilded vessel
#

its important to note the domain isnt actually changing for x

#

its like if you had x = a

#

multiply by 2

#

2x = 2a

#

its the same equation

real rune
#

yeah

#

i see

#

that makes a lot of sense

#

thanks so much B)

gilded vessel
#

np

real rune
#

okay well ill go back to doing more work B)

#

.close

lone heartBOT
#
Channel closed

Closed by @real rune

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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

naive flare
lone heartBOT
naive flare
#

I'm not sure how to start this or how to solve it even

gray isle
#

approach it in the same way as you would when finding intersections of simpler lines

#

you'll have a quadratic equation in one variable

#

and you can use something like the quadratic formula

naive flare
gray isle
#

sub back into either original equation to get the respective y coordinates and hence points

naive flare
#

sub back into the standard form?

#

to find the POI?

gray isle
#

wdym into the standard form

naive flare
gray isle
#

either original equation

#

you were given 2 equations

#

sub the x-coords you found into either one of them

naive flare
#

so any of the x-intercepts I found, I can put just one in into one of the original equations

gray isle
#

each x-coord you found gives you a point

#

subing first x-coord gets you its y-coord giving you one of the points
subbing the second x-coord gets you its y-coord giving you another point

naive flare
#

ok

#

thanks

#

.close

lone heartBOT
#
Channel closed

Closed by @naive flare

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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

crisp prism
#

The resistance, R, to electricity of a cylindrical-shaped wire is given by the equation R = pL/πd^2, where p represents the resistivity of the wire’s material, L represents the length of the wire, and d represents the diameter of the wire. What happens to the resistance of the wire as the diameter approaches 0?
The resistance approaches 0.
The resistance approaches Pi.
The resistance approaches L.
The resistance approaches infinity.

raven haven
#

show work

crisp prism
#

I haven't written anything

#

I don't really understand what to do

raven haven
#

Can you try something first?

#

,w plot 1/d^2

crisp prism
#

ok so

#

I know that when d approaches 0, it becomes undefined

raven haven
#

undefined?

#

or infinity

crisp prism
#

anything divided by 0 is undefined right?

raven haven
#

well

#

Here you don't see "the resistance is undefined"

#

lim x->0 1/x is undefined because the limit doesn't exist

#

But if you look at said plot what do you notice

crisp prism
#

the y values approach infinity?

#

oh

#

OH

raven haven
#

yep

crisp prism
#

ok thank you so much

raven haven
#

np

crisp prism
#

.close

lone heartBOT
#
Channel closed

Closed by @crisp prism

Use .reopen if this was a mistake.

quasi venture
#

How do I open

lone heartBOT
#
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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

real rune
lone heartBOT
real rune
#

how do i do this question?

raven haven
#

tan (2x) = sin2x/cos2x

#

Try to turn it into something that looks like a polynomial first

raven haven
ocean sealBOT
real rune
#

8cos^2x - cos/sin - sin2x/cos2x

#

can i cross out a sin and cos? im assuming no right

raven haven
#

Nope

#

Because they can be 0

real rune
#

mm ok

raven haven
#

$8(\cos x)^2 - \frac{\cos x}{\sin x} - \frac{\sin 2x}{\cos 2x}$ = 0

real rune
#

ye thats what i have rn

ocean sealBOT
raven haven
real rune
#

do i really have to expand it all though?

raven haven
#

Get rid of the sin 2x and cos 2x

#

Well

real rune
#

theres prob a faster way right

raven haven
#

I don't know

real rune
#

cus like my immediate thought was to do that but i feel like theres a faster way to do it

raven haven
#

I mean why not do that then

real rune
#

and less tedious

raven haven
#

Well here's how I'll do it faster:

#

,w tan2x = 8 (cosx)^2 - 1/tanx

real rune
#

uh

raven haven
#

yeah lol

real rune
#

what

#

LMAO

raven haven
#

That's called "cheating"

#

Just expand it out

real rune
#

okay

raven haven
real rune
#

yeah

#

k so i expanded them out

#

but like now we have to common denominator and everything right

#

there is 100% a faster way to do this

#

without all these steps\

raven haven
real rune
#

no like

#

when an equation is like this

#

theres a faster way to do it

raven haven
#

how do you know that

#

did someone tell you there is

real rune
#

well i mean

#

its just math

raven haven
#

or is it just a gut feeling

real rune
#

its neither

#

its an educated guess PepeLaugh

raven haven
#

I'm not aware of any faster way

#

You can check with your teachers

real rune
#

hm

#

well i guess i just have to multiply it out then

#

unfort

minor needle
#

I'm not sure you'll be able to solve for exact forms, maybe Weierstrass substitution will be required thinkies

raven haven
#

I think they wouldn't have learnt that lol

real rune
#

yeah

#

i hvae not

raven haven
#

well then

real rune
#

yeah no its def not correct

#

because it gives a huge fraction

raven haven
#

does not immediately mean it's not correct lol

real rune
#

not factorable

#

no like its

raven haven
#

oh well that's suspicious

#

can you show?

real rune
#

8sinxcos2xcosx^2 - cos2xcosx -sinxsin2x/sinxcos2x

minor needle
#

I'd do it on the paper, I'm curious

real rune
#

oh

#

this is what i have rn

#

its loading

#

ignore the stuff on the top\

#

that was from the previous question

minor needle
#

oo I have cool form

real rune
#

wdym

#

oh btw i dont know hwy but i alternate between theta and x

#

bad habit of mine

minor needle
#

I've got

#

equivalent form

#

as

ocean sealBOT
real rune
#

wait where does this occur?

#

im blind

minor needle
#

some trig identities and that's it

#

and I see it works

real rune
#

like the inside is cos4x right

#

wait what

minor needle
#

aa

#

but still not

real rune
#

hm

minor needle
#

it's not cos(4x)

real rune
#

oh wait its not squareed

#

square

#

squared

#

mb

minor needle
#

cos(4x) would be 1 - 2sin^(2x)

real rune
#

ye

#

i didnt see there was no square mbmb

minor needle
#

np, now

#

lemme write my work out

#

and from here it's easy to solve

real rune
#

wait why do u multiply by sin x on both sides

minor needle
#

I can do it since cot(x) provides that sin(x) isn't 0

real rune
#

wait what

minor needle
#

and main problem is sin(x) in the denominator, we want to have no fractions there

#

so this is why

real rune
#

also i got the answer after

#

bt im still conbfused in your process

#

the answer is pi/24 and 5pi/24

#

but

#

like going from

minor needle
#

and pi/2 also

real rune
#

step 1 to 2 after the multiply both sides by sinx

#

no pi/2 wouldnt be one

#

oh i forgot

#

to mention the range

#

i mean domain

#

its 0 <= x <= pi/4

#

but from ur work idk how u go from step 1 to 2 after the sinx multiplicatin

minor needle
real rune
#

oh wait the fk?

#

i wrote pi/4 on my sheet

#

MB

#

MB

minor needle
#

ye

real rune
#

LMAO

#

but anyways

minor needle
real rune
#

where does the -sinx come from

#

oh wait

#

did u use the

#

identity

minor needle
#

I've multiplied by sin(x) and that's it

real rune
#

wait no

minor needle
#
  • was there
real rune
#

wait what

#

OHHH

minor needle
#

in the last few lines I've used sin(2x) twice

real rune
#

wait but then

#

how does this portion work

#

like when u multiply

#

cos2x into 8cos x

#

and 1/sinx

#

how do u get cos2x + cos 2x

minor needle
#

sin(x) * 1/sin(x) = 1

#

so from sin(x) * cos(2x) * 1/sin(x) you have cos(2x)

#

and 8 * sin(x) * cos(x) * cos(2x)

#

I've used sin(2x) = 2sin(x)cos(x)

#

and fact that 8 = 4 * 2

real rune
#

also

#

when u multiply sinx into 8cosx

#

how does that become 8sinx

#

by itself

#

idk this work blows my mind so i dont really know what im looking for tbh

minor needle
#

Multiplication is commutative.

real rune
#

more of a brain gap tbh

#

im not smart enough to comprehend it all

minor needle
#

then if you have sin(x) * 8cos(x)

#

u can rewrite this as 8 * sin(x) * cos(x)

#

it's same thing

#

like a * b * c = b * a * c

real rune
#

oh

#

i see

#

thats where the other cos x came from

#

ok

#

so now

#

how does the cos2x * 8cosx - 1/sinx work again

#

u did like

#

cos2x * 4cosx * 2 cosx right

#

or something

minor needle
minor needle
#

look at this

ocean sealBOT
real rune
#

ohhhhh

#

i see

#

just gonna send this again so i dont have to scroll up

#

one last thing

#

how does cos2x * 1/sinx work again?

#

o-o

#

i understand EVERYTHIGN else tho

#

B)

minor needle
#

not cos(2x) * 1/sin(x)

real rune
#

oh

#

so then its just 1 x cos2x

minor needle
#

ye

real rune
#

OH MY GAH

#

ok so uh

#

i guess that odes it for that question

#

just quick question how much time do u have

#

cus i dont wanna keep u here too long if ur busy

#

nvm i think im good

#

thanks so much for ur time and patience with me B)

minor needle
#

it's fine

real rune
#

.close

lone heartBOT
#
Channel closed

Closed by @real rune

Use .reopen if this was a mistake.

lone heartBOT
#
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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

lyric fable
lone heartBOT
lyric fable
#

is this correct?

#

a simple yes or no would do

alpine sable
#

Yes

raven rover
#

Yes

#

Good to go 👍

median oar
#

i wonder if the 3rd side being 4 counts as a triangle

alpine sable
#

Do this for me please

median oar
#

it will still have 3 sides and have all the angle properties of a triangle

waxen osprey
#

Consider the triangle inequality

lyric fable
#

thanks guys

median oar
#

yeah but is a triangle that's stretched to a line not a triangle

#

$z\leq x+y$

ocean sealBOT
#

Frosst

median oar
#

wikipedia writes this

sage jolt
#

help me describe the solution

waxen osprey
#

z=x+y is not a triangle it is a line

median oar
#

a degenerate case for the triangle is still a triangle is it not?

median oar
waxen osprey
#

if is a line

#

it*

median oar
#

the degenerate case of a triangle still does have 3 sides

#

they just happen to lie on the longest side of the triangle as well

waxen osprey
#

well can you have a triangle with no area

median oar
#

well yeah why not

#

any 3 points in 2D space can make a triangle

#

even if 2 or 3 of the points are on top of each other

waxen osprey
#

In Euclidean geometry, any three points, when non-collinear, determine a unique triangle and simultaneously, a unique plane

median oar
#

or are collinear

waxen osprey
#

from wiki

median oar
#

that doesn't say it's not a triangle

#

that just says it's not a unique triangle and does not simultaneously determine a unique plane

waxen osprey
#

I see your point but it wouldnt get the person asking the marks

#

its just to do with definition

median oar
#

i was just curious to see if a degenerate triangle is a triangle

#

and it seems so

lone heartBOT
#

@lyric fable Has your question been resolved?

waxen osprey
#

Wait does that mean a triangle is a degenerate quadrilateral ?

#

if you let one of the points be on the side of the triangle?

lone heartBOT
#
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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

nimble estuary
#

Angle A is trisected. Find the length of the shortest side in triangle ABC. I’m really stuck on this, stuff in this unit is generally law of cosines but I can’t seem to figure out if that’s possible.

pliant cedar
#

,rotate

ocean sealBOT
pliant cedar
#

maybe the law of sines can help?

nimble estuary
#

wouldn't I need at least an angle?

#

what about angle bisector theorem multiple times?

lone heartBOT
#

@nimble estuary Has your question been resolved?

nimble estuary
#

<@&286206848099549185>

alpine sable
#

Sup

nimble estuary
#

hello

alpine sable
#

Tried triangular inequality?

nimble estuary
#

how would that work with only one side?

tepid jungle
#

Ya got a ratio

nimble estuary
#

i did bisector angle then attempted stewarts

alpine sable
#

Lemme try

nimble estuary
#

I put point D in between 2 and 3 and point E between 3 and 6 btw

#

I think if I do stewarts and make a system it could work but idk how i would make the system

tepid jungle
#

This is the idea you want

#

Oh you’re wanting the short side, but still same idea

#

Oh my math bad, gimme sec

nimble estuary
#

what i l1 here?

#

wouldnt law of sines be sin(angle1)/a

pliant oak
#

Set B-D-E-C colinear
AD is the line bisects ∠BAE
AE is the line bisects ∠DAC
Then
AB:AE=BD:DE=2:3
AD:AC=DE:EC=1:2
Set AB=2x,AE=3x,AD=y,EC=2y
∠BAD=∠DAE=∠EAC=z
Then by law of sine
2/sinz=y/(sin∠B)
5/sin(2z)=3x/(sin∠B)
11/sin(3z)=2y/(sin∠B)
3/sinz=3x/sin(∠B+z)
4 equations,4unkowns
But it is too complicated to solve

nimble estuary
#

so just no answer?...

pliant oak
#

Maybe use law of cosine in ∠B or z can list equations more easily to solvethonk

#

Solve these equations to reach the answer but it‘s hard lol😩

carmine reef
#

Ah I've seen this problem before

#

Exact same one with the exact same side lengths

#

Twice before

nimble estuary
#

really

carmine reef
#

Kinda forget tho

nimble estuary
#

😭

carmine reef
#

Once on a high school math club comp and once in an aops book

#

You have to set one side length to x I think

#

If you choose AB then AE is 3x/2

#

I suppose you could say AD is y and AB is 2y and try stuarts

#

Maybe Stuarts with triangle ABC and both the AD and AE cevians

#

iirc the algebra somehow is actually ok

nimble estuary
carmine reef
#

One at a time

nimble estuary
#

ah

carmine reef
#

system of equations 😭

nimble estuary
#

using AB and AC as the outer lines or AB and AE to find AD

carmine reef
#

but its ok I think

carmine reef
#

If you know that one you can do it that way instead

#

But in essence we are finding every single cevian of every single triangle and performing Stuarts on it lol

nimble estuary
#

i didnt even know stewarts til about 30 minutes ago lol

carmine reef
#

It be like that

#

a man and his dad put a bomb in the sink

#

man + dad = bmb + cnc

#

lol

nimble estuary
#

i would add DE and EC?

carmine reef
#

Are you doing Stuarts on CDE?

#

Or wait no lol

#

ACD

nimble estuary
#

I'm doing it on cevian AD

#

i thought u said use triangle ABC 💀

carmine reef
#

oh

#

No that's right ok

nimble estuary
#

i get like

#

(2x^2+48y^2)/11-16

carmine reef
#

Yes CD = CE + ED

nimble estuary
#

good lord theres no way im doing this right

carmine reef
#

m = 2, n = 9, right

#

a = 11

nimble estuary
#

i did math wrong

carmine reef
#

b = x, c = 2y

nimble estuary
#

2x^2+36y^2

#

yep

carmine reef
#

I think unless I've swapped m and n

nimble estuary
#

BD=m=2

#

DC=n=9

#

i got (2x^2+36y^2)/11-16

#

=y^2

#

and (2x^2+36y^2)/11-30=(9x^2/4)

#

this seems really bad

carmine reef
#

198 + 11y^2 = 2x^2 + 9y^2 is what I get

#

,w Stuarts theorem

nimble estuary
#

bruh

carmine reef
#

Oh c and b are swapped

#

Or m and n are

nimble estuary
#

ohhh

#

b and c are

#

waitno

carmine reef
#

Well making either swap makes it work

#

symmetry

nimble estuary
#

ohhh

#

i see

carmine reef
#

b = 2y, c = x

#

man + dad = bmb + cnc

#

198 + 11y^2 = 8y^2 + 9x^2

#

I think

nimble estuary
#

whats d in this case

carmine reef
#

If you want you can even treat this as a linear equation in x^2 and y^2 and then solve for x^2 and y^2 once you do the other one

carmine reef
nimble estuary
#

the cevian?

#

ah

#

yeah i got what you got

carmine reef
#

nice

nimble estuary
#

330+(99x^2/4)=20y^2+6x^2?

carmine reef
#

That's what I get too

nimble estuary
#

great now

#

system...

#

uh

#

do i multiply smth

#

do cancel out a variable

carmine reef
#

Probably add the systems together to cancel out the ys

nimble estuary
#

yeesh

#

that math is nasty

#

multiply by 4 and 2

carmine reef
#

Well first you cancel like terms

#

Or you can do substitution if you want

#

I recommend going about it in a way that you'll solve for x

#

Since the shortest side is definitely either x or 11

nimble estuary
#

ok

#

198=-3y^2+9x^2

#

and 330=20y^2-(75/4x^2)

carmine reef
#

Divide all terms of 1st equation by 3

#

66 = -y^2 + 3x^2

nimble estuary
#

you just saved me a lot of time

carmine reef
#

:D

nimble estuary
#

1650=165/4x^2

#

x^2=40

carmine reef
#

330 = 60x^2 - 1320 - 75x^2/4

#

1650 = 165x^2/4

#

so yr

#

ye

nimble estuary
#

i got an imaginary num for y lmao

carmine reef
#

120-66

nimble estuary
#

oh

#

lmao i did it weird

carmine reef
#

hopefully y = sqrt(54)

nimble estuary
#

yup

#

oml that took me an hour

#

i have a problem solving test tmr

#

and we get 100 minutes

#

for 4 questions like this

carmine reef
#

Oof

#

Competition math?

nimble estuary
#

nope

#

just a plan ol

#

honors precalc bc

#

final

#

theres no set curriculum cause its not AP

#

so he just does whatever he wants

carmine reef
#

oof

#

gl

nimble estuary
#

my math teacher is lowk psycho lmao

#

giving us induction proof and stuff within a week of starting

#

no idea how people like math

#

no offense lol

carmine reef
#

lol dw

#

that's rough

#

Proof writing is a pain to get into for sure

nimble estuary
#

i like proofs but not computing

carmine reef
#

oh yeah thats pain too

#

For a problem like this it's rough because unless I get into the computational mess to some degree it's not clear that the method I'm thinking of will work

carmine reef
nimble estuary
#

dyk geometric series

#

91=7(1-r^6)/1-r

carmine reef
#

That seems like a degree 6 polynomial equation

#

Geometric series or not

#

I severely doubt it has a rational solution

#

You can factor a 7 out idk what else to do

nimble estuary
#

is there a diff way to go abt it
given
a+ar=7
a+ar+...+ar^5=91

#

thats the original problem

#

and the question asks to find the sum of the first 4 terms

carmine reef
#

yeah

#

Original equation isn't right I don't think

#

Then

nimble estuary
#

yeah its not

carmine reef
#

(a+ar)(1+r^2+r^4)

nimble estuary
#

i got r^4+r^2+1=13

carmine reef
#

(idk how to call it but this is a factorization you'll sometimes run into, it works for geometric series of any composite length)

carmine reef
nimble estuary
#

now what tho

carmine reef
#

There's a useful substitution

#

You see these a lot for solving high degree polynomials that would otherwise seem nearly impossible

nimble estuary
#

just substitute x for r^2?

carmine reef
#

ye

#

exactly

nimble estuary
#

x=-3,4

scenic crescent
#

pls help w 2 i've done 1

nimble estuary
#

.

nimble estuary
#

is it even possible for -4=x

#

wouldnt that be imaginary

carmine reef
#

Yeah

#

it would be imaginary

nimble estuary
#

so r=sqrt3?

carmine reef
#

So we have a case where a geometric series with imaginary components ends up having certain real partial sums

#

But presumably we're not talking about imaginary sequences so we can ignore the solution

#

r = sqrt(3) should work

nimble estuary
#

i got a=14sqrt3/3

#

thats some ugly numbers

carmine reef
#

I don't think that's right

#

What did you do?

nimble estuary
#

a+ar=7

#

substituted r

#

divided 7 by r

#

and divided that by 2

carmine reef
#

a+asqrt(3) = 7

nimble estuary
#

yes

#

so 2a=7/sqrt3

#

rationalized

carmine reef
#

no

nimble estuary
#

no?

carmine reef
#

a + asqrt(3)

#

What would happen if we divided that side by r

nimble estuary
#

it would end up a/sqrt3?

#

factor out a?

carmine reef
#

(a+b)/c is not a + (b/c)

nimble estuary
#

a=7/1+sqrt3

#

?

carmine reef
#

with parentheses yes

nimble estuary
#

yeah

carmine reef
#

could rationalize if u want not too important

nimble estuary
#

-(7-7sqrt3)/2

#

even worse than before

carmine reef
#

yeah

#

hopefully this one should work tho

nimble estuary
#

thats weird

#

i got 112+112sqrt3

#

wait no

#

its 28

carmine reef
#

for what?

#

first 6 terms sum?

nimble estuary
#

4 terms sum

#

i actually coulda just

#

found r

#

then subtracted a+ar from 6 term series

#

then divide by r^2

#

to get sum

carmine reef
#

(a+ar)(1+r^2) too yeah

#

7*4

lone heartBOT
#

@nimble estuary Has your question been resolved?

#
Channel closed

Closed by @nimble estuary

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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

spare fern
#

hey guys

lone heartBOT
spare fern
#

could someone help me out with this question

#

8m/ square root of m

vague mirage
#

$8m^{1-1/2}$

ocean sealBOT
#

Arnab Pal

spare fern
#

its a fractional powers question and I'm not sure how to write what it is equivalent to

vague mirage
#

It is

spare fern
vague mirage
#

Yeah

#

$8m^{1-1/2}$

ocean sealBOT
#

Arnab Pal

vague mirage
#

What is 1-1/2?

spare fern
#

1/2

vague mirage
#

Yeah so 8√m

#

Is the answer

#

Cause ^1/2=√

#

You know what I mean

#

Laws of exponents

spare fern
#

oh I see

#

thanks

vague mirage
#

Yes

#

Wlcm

spare fern
#

are you really taught this at 14?

#

.close

lone heartBOT
#
Channel closed

Closed by @spare fern

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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

alpine sable
#

do you know how to calculate 8 - (-15) ?

vague mirage
#

It is that easy

#

Bope

alpine sable
#

no

vague mirage
#

Nope*

#

8-(-15)

#

What's -1×-1

#

$-1×-1$

alpine sable
#

because subtraction is not commutative

ocean sealBOT
#

Arnab Pal

alpine sable
#

order matters

vague mirage
#

Yupp

alpine sable
#

or at least you would have to write it as -(-15)+8

vague mirage
#

Nooo

#

It wasn't right

#

What is 8-(-15)

#

Actually tell me what's 8+15

#

Yeah that's it it's the range

#

Yess

alpine sable
#

also it's important to note that range cannot be a negative number

#

because you are subtracting the lowest number from the highest number right

#

therefore it's always a positive number

#

both B and D are negative numbers

#

therefore you can immediately know that they are wrong

lone heartBOT
#

@dusty spire Has your question been resolved?

#
Channel closed

Closed by @dusty spire

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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

warped berry
#

Hello guys, I have a question regarding to potence series and the radius of convergence. Maybe somebody can help me out with the following exercise where you have to determine the radius of convergence

warped berry
#

I'm just unsure how to solve this problem. I know that this is the harmonic series

rose sigil
#

it's def at most 1 bc it diverges when x=1

#

i haven't done anything yet but i'd guess it converges when 0 < x < 1

#

maybe you can compare it to smth

#

like a geometric series

keen plinth
#

ig ratio test?

rose sigil
#

oh yea i think that'll do it for when 0 < x < 1

hollow plover
rose sigil
#

,rotate

ocean sealBOT
lone heartBOT
#

@warped berry Has your question been resolved?

lone heartBOT
#
Channel closed

Closed due to timeout

Use .reopen if this was a mistake.

lone heartBOT
#
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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

halcyon delta
#

Hey, thanks in advance for the time people spend on solving this problem, I really appreciate it!

The gps system requires 4 satellites to determine the position of a point, however, a satellite must orbit the planet and the planet must not be between the satellite and the point in order to be able to reach the planet. The question is: given a radius of the planet and the radius of circle the satellites are orbitting in, how many satellites are needed such that every point on the planet can be seen by at least 4 satellites at all times?

I’ve solved the problem already in 2 dimensions, where 3 satellites are needed instead of 4; see picture

halcyon delta
limpid turret
#

assuming general relativity is not considered

halcyon delta
#

yeah

green folio
#

The legendary help 0

limpid turret
#

"a satellite must orbit the planet and the planet must not be between the satellite and the point in order to be able to reach the planet"

halcyon delta
#

I’ve called the distance where a satellite can be in ‘o’. and the radius of the satellite, r2, I’ve set to 1. o = pi - sin^-1(r1/1)

limpid turret
#

What does this mean

limpid turret
#

gotcha

#

So for any point in 3d, you need 4 satellites in that valid range, yeah?

halcyon delta
#

yes

#

and in 3D, the part where the satellite must be in to see a certain point is a cut sphere

limpid turret
#

and I'm guessing the number of satellites is variable based on the two radii

halcyon delta
#

yeah

limpid turret
#

Interesting problem

halcyon delta
#

wel technically the ratio between the two radii

#

I agree

limpid turret
#

Ratio of the radii should create an invariant

halcyon delta
#

err yeah ratio*

tribal haven
#

this does not feel at all easy and my brain keeps going to infinitely far away satellites in which case you only need 8thinkies

but i guess you can try to cover the sphere using several circular patches where you stack 4 satellites on the same point at a time

limpid turret
#

My intuition is thinking:

#

Total solid angle of a sphere is 4pi

#

Figure out how much solid angle a single satellite covers

#

Then you need 4 satellites in that solid angle

halcyon delta
#

by the way here is some clarification on the 2D version of the problem

limpid turret
#

It's 3am here so I cannot offer much more discussion

#

But I will probably ruminate on this in my sleep

#

Feels free to DM me as I find this problem interesting.

halcyon delta
#

thanks! you should go to bed xD

alpine sable
#

what does

#

ruminate mean

halcyon delta
#

you should ask your question in one of the listed available help channels

halcyon delta
alpine sable
green folio
#

To think extensively abt it

halcyon delta
limpid turret
keen plinth
#

some kind of sphere covering problem

#

getting upper and lower bound is easy

#

but theyre pretty far apart

halcyon delta
#

the radius of the circle that the satellite have to be in is pi-2*sin^-1(r1/1) if you take the distance as having to walk over the big sphere and r2=1, is that what you mean?

halcyon delta
keen plinth
#

i mean you can work out a rough lower bound and upper bound on how many satellites you'd need

#

but they can be quite far apart meaning theyre basically useless

halcyon delta
#

true, what makes it difficult is the many ways you can arrange the orbits, even if you assume the orbits are in the shape of a circle

lone heartBOT
#

@halcyon delta Has your question been resolved?

lone heartBOT
#

@halcyon delta Has your question been resolved?

lone heartBOT
#

@halcyon delta Has your question been resolved?

lone heartBOT
#

@halcyon delta Has your question been resolved?

opal sphinx
#

H

lone heartBOT
#

@halcyon delta Has your question been resolved?

lunar bluff
#

Value x equation 4(6x-9.5)=46

halcyon delta
#

if you do, im willing to help you with it. Feel free to ping me

halcyon delta
#

<@&286206848099549185> any chance you could have a look at this problem?

last ether
#

Why not make a square around the earth, place four satellites on the corners, then rotate that square 45° and then place 4 more

#

Oh wait nvm that won't work

#

Big brain moment

raven haven
#

,w gps satellite coverage

ocean sealBOT
raven haven
#

welp

lone heartBOT
#

@halcyon delta Has your question been resolved?

left crypt
#

@halcyon delta are you still looking for some help here?

bold gate
#

i need help

#

badly

#

i feel so stupid

#

i dont belong here

#

i suck at math

left crypt
#

@bold gate open a help channel.

bold gate
#

idk why i try anymore i just wantt o drop out of life

#

how do i do that

left crypt
#

Don't hijack open help threads.

bold gate
#

what does hjiack mean

#

im new here

left crypt
#

maybe read the instructions. Like #rules

bold gate
#

thats the question i need help with

left crypt
#

Stop posting here.

bold gate
#

i dont get it

left crypt
#

This is someone else's help thread.

bold gate
#

ok how do i delet eit

left crypt
#

Follow the instructions in #rules and open your own channel.

#

Anyway @halcyon delta :

I have some pointers to help you frame the problem a bit better if you are still looking for help

-you don't really need to consider the orbits of the satellites for the coverage problem; a static arrangement is sufficient.

-any particular satellite cannot see past the great circle arc which forms the plane orthagonal to the line between the satellite and the center of the globe (i.e. coverage is a hemisphere assuming sufficiently wide field of view, precision, and distance from the earth)

-it's relatively simple geometrically to construct a pattern which clearly provides quadruple coverage to the whole planet; the tricky part is showing when the removal of any additional satellite makes complete surface coverage impossible--ideally, you would like to construct a minimal coverage pattern that has exactly 4x coverage along each point except possibly some great circle arcs, such that clear removal puts you below the lower bound of coverage (namely: total coverage < 4x surface area of the earth, or in other words an arrangement that does it with exactly 8 satellites.

#

The problem becomes more complex if you limit ranges and fields of view, but if you construct the mathematical relationships for the minimal cover it should become apparent how to start attacking the more restrictive variant...

halcyon delta
left crypt
#

so, if you read through, I was trying to lead you through a process to illuminate the "more restrictive problem".

#

if you think about the symmetries of a sphere and an orbit, the same notions that take you from an unrestricted field of view to a restricted one are the same notions that solve the orbits problem. In the words of Polya: solve a simpler problem first.

#

(Think in radians about how a narrowed field of view changes the math on the static problem and then consider the symmetries of an orbit and a sphere and how the angular sweeps of those symmetries interact)

lavish oyster
#

,w a_1+4a_2=6, a_2+4b_1=-3, a_1+b_1=1

lone heartBOT
#

@halcyon delta Has your question been resolved?

#
Channel closed

Closed by @halcyon delta

Use .reopen if this was a mistake.

lone heartBOT
#
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.
After 15 minutes, feel free to ping <@&286206848099549185>.
• 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.

strong flame
#

Hey

lone heartBOT
strong flame
#

can i get some help?

#

how do i calculate the maximum and minimum value of this function:

#

5sinx - 12cosx

#

my idea was to make:

#

5*sqrt(1 - cosx^2) - 12cosx

#

so its only cos

#

but what now?

worn fox
#

Perhaps a more helpful method might be to write it in the form Rsin(x+α)

long axle
#

Bruh

worn fox
#

Please put a disclaimer if you're going to use chatgpt

strong flame
#

is it possible without derivatives?

worn fox
#

You know the max an min values of just a sin function

strong flame
#

-1; 1

worn fox
#

So you need to find R

#

Wow so helpful

strong flame
#

how do i find 'R'

worn fox
#

Expand out Rsin(x+α), and set equal to your original expression

#

Using angle sum formula^ that'll let you find R

#

This stuff is called "harmonic form"

#

Okay you should probably go elsewhere

#

<@&268886789983436800> 🤷‍♂️

strong flame