#help-0

1 messages · Page 275 of 1

lone heartBOT
#
Channel closed

Closed by @hard aspen

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.

safe tartan
#

cos(picosx)=0 for -pi/2 to pi/2, i tried rewriteing the domain for picosx

safe tartan
#

and i got x is larger than 0 but less than 0

near apex
#

Woah

#

Show.

safe tartan
#

i jsut did

#

picos(-pi/2) < picosx < picos(pi/2)

#

maybe you dont do this for when you apply cos but not sure

winter light
#

Can you send the original question? @safe tartan

safe tartan
#

cos(picosx)=0 for -pi/2 to pi/2 solve for x

#

isnt cos(-pi/2)=0

winter light
near apex
#

It is.

near apex
near apex
safe tartan
#

monotone as in continuously decreasing/increasing?

safe tartan
#

right

winter light
# safe tartan picosx=pi/2 + kpi right

So πcos(x) = π/2 + kπ, hence cos(x) = 1/2 + k. Since -1 ≤ cos ≤ 1, k (which is an integer) must be 0, giving you cos(x) = 1/2, that happens at x = ±π/3

safe tartan
#

k could be -1 right

near apex
safe tartan
#

i mean im not doing it for answers though just tryna learn

winter light
#

I didn't just give the solutions, but also the method to get them

near apex
winter light
safe tartan
#

when i solve cosx=1/2 and cosx=-1/2

#

which domain am i following

near apex
#

Either just directly find solutions from your domain.

#

Or find general solutions and take intersection with domain.

safe tartan
#

yep i think i got it, thanks

#

.close

lone heartBOT
#
Channel closed

Closed by @safe tartan

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
lone heartBOT
alpine sable
#

I have no idea how to solve this

#

my idea was taking two arbitrary points

#

then measuring the surface area with both and seeing if i get teh same result

#

but idk if that's correct

near apex
#

You are on right track. Just take two varible points (x1,y1) and (x2,y2) and calculate surface area for both.

#

You'll come to see that their area is same.

alpine sable
#

oh so it's right

near apex
#

Surface area of triangle is just area of triangle or perimeter ?

alpine sable
#

1/2 x b x h

near apex
#

Alright.

#

Then yeah, do that.

alpine sable
#

Alright another question but simpler

#

I managed to find the point where the two lines cross but

nimble latch
alpine sable
#

how do i find the tangent line equation's slope

alpine sable
near apex
nimble latch
#

right, i see

vale crag
#

That's what the condition for two graphs touching boiks down to

alpine sable
#

yeah but

#

what i did was plug -1 into y = x^2

#

and then did 1 = (-1)(-1) + b which is wrong i think

#

like i managed to find the point by equating the derivatives

#

then plugging -1 into the original formulas

#

yeah idk where to go from here

vale crag
#

Yeah idk what you're trying to do here

#

Just check the two functions have the same derivative for x=-1

#

If they do, you won

alpine sable
#

@vale crag

#

I wanna find the tangent line

#

that relates to these two points

#

but i have no clue how

vale crag
#

The slope of the tangent line is the derivative

#

As usual

alpine sable
#

so you're saying

#

2(-1) = -2

#

for the eslope

#

1 = -2(-1) + b

#

b = -1?

vale crag
#

Yeah

alpine sable
#

alright tysm

#

🫡

#

.close

lone heartBOT
#
Channel closed

Closed by @granite ether

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.

thick monolith
#

i have question about definition of f(x)=e^x

tardy tapir
#

yes?

thick monolith
#

So in a math book im studying from rn I get the definition for f(x)=e^x where all real x values are allowed and result definition as y > 0

#

im not sure if the word definition is correct here btw, studying in swedish

foggy copper
#

definition is fine here yea

vale wigeon
#

you're using the word in two different senses

#

the INPUT set of e^x is the entire number line.

thick monolith
#

Df=xeR and Vf=f(x)>0

vale wigeon
#

the OUTPUTS on the other hand are only positive

thick monolith
#

right, outputs ill use that word

vale wigeon
#

in english they're called domain and range respectively

thick monolith
#

Okay so outputs allowed are defined as greater than 0

foggy copper
#

provided your input was real, yes

thick monolith
#

but than I have a function f(x)=e^x-1

vale wigeon
#

$e^x - 1$ or $e^{x-1}$?

ocean sealBOT
thick monolith
#

first one

vale wigeon
#

ok

thick monolith
#

So output should now be greater than or equal to 0

vale wigeon
#

no

foggy copper
#

no

vale wigeon
#

that's only for e^x itself

thick monolith
#

i think, since if I set x=0 than I get f(x)=0

vale wigeon
#

no, the range of e^x itself is (0, +∞).

#

but the range of e^x - 1 is obviously shifted down by 1 from that, so (-1, +∞).

foggy copper
thick monolith
#

(0, +∞) <- dont really understand this part

vale wigeon
#

it's the interval from 0 to +infinity

#

do you know about interval notation

#

if not i will have to translate that back into inequalities

foggy copper
thick monolith
#

i dont

#

inequalities might be more readable for me

vale wigeon
#

the range of e^x itself is y > 0

thick monolith
#

right

vale wigeon
#

but the range of e^x - 1 is shifted down 1 from that

#

so y > -1

thick monolith
#

okay that makes sense

#

and now I also see I actually misread one of the solutions in the book

#

thank you for the help :d

lone heartBOT
#

@thick monolith Has your question been resolved?

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.

dapper verge
lone heartBOT
dapper verge
#

Could I get help on question 14?

vale wigeon
#
Four steel discs, each with radius 1 cm, are placed in a square frame as shown.

(a) Find the length of the sides of this frame.
(b) In order to brace the frame, a diagonal support is to be added to the frame. Find the length of this support.
(c) Find the length of material needed to build the frame, including the diagonal brace.
#

which part is troubling you?

dapper verge
#

I dont get how'd you find the length of the frame? Would I add the 1cm together or ?

#

and then apply pythag?

vale wigeon
#

are you talking about part a or part b here or what

vale wigeon
#

right

#

you don't need pythag for part a just yet

#

it is just visible that the side of the outer square is twice the diameter of each circle

dapper verge
#

so 1 cm?

#

sorry im dumb lol

vale wigeon
#

no, it is not 1 cm.

#

1 cm is the radius of each circle.

#

what's the diameter?

dapper verge
#

half the circle

vale wigeon
#

you're not only not answering my question, you're also wrong.

dapper verge
#

isnt the diameter just a straight line that goes through it?

vale wigeon
#

"it"

dapper verge
vale wigeon
#

...

#

no, "a straight line that goes through the circle" does not describe the diameter.

#

and you still haven't answered my question:

what is [the length of] the diameter of a circle whose radius is 1cm?

dapper verge
#

2 cm

vale wigeon
#

ok

#

and what's twice that?

dapper verge
#

4cm

vale wigeon
#

exactly

dapper verge
#

and for be would it be:
c^2 = 8^2 + 8^2
c^2 = 64 + 64
c^2 = 128

vale wigeon
#

why 8

#

we just found that the square has side length 4 cm

#

so why 8 all of a sudden

dapper verge
#

as its four wouldnt u double it for each side?

vale wigeon
#

...come again?

#

i don't understand what you're saying

dapper verge
#

nvm i messed it up

#

c^2 = 4^2 + 4^2
c^2 = 16 + 16
c^2 = 32

vale wigeon
#

that sounds a lot better now

dapper verge
#

.end

#

.close

lone heartBOT
#
Channel closed

Closed by @dapper verge

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 moon
#

Imagine a gambling game, my probability of losing is 1/25, I have to play this game 10000 times. What is my probability of losing at least 240 times?

near apex
#

!status

lone heartBOT
#
What step are you on?
1. I don't know where to begin
2. I have begun but got stuck midway
3. I got an answer but I'm told it's wrong
4. I got an answer and would like my work checked
5. I have a question about someone else's worked solution
6. None of the above
crisp moon
#

1

near apex
#

How many ways can you lose 240 games out of 10000 games ?

crisp moon
#

My chance of losing each round is 1/25 (4%) im playing this game 10000 rounds. What is the probability of me losing at least 240 times in total?

#

Briefly chance of losing at least 240 out of 10000 rounds

near apex
#

Do you know what losing at least 240 games imply ?

crisp moon
#

it means all my money is gone

near apex
#

Lol. I meant what cases does it include.

crisp moon
#

Sorry im not a mathematician xD

near apex
#

I just want to ensure that you understand this:
Losing at least 240 games means that you lost 240 or more games.

#

Not exactly 240.

crisp moon
#

"Losing at least 240 games means that you lost 240 or more games." yes this is

#

not 240

near apex
#

is that clear?

crisp moon
#

yes

near apex
#

Good.

#

So we need this probability actually.

probability of losing exactly 240 games + probability of losing exactly 241 games + probability of losing exactly 242 games + ... + probability of losing exactly 10000 games

crisp moon
#

oh yes this makes sense

#

thank you

near apex
#

Okay.

#

Should i go on or do you wanna try this on your own first ?

crisp moon
#

oh you better do it i'm not very good at math

near apex
#

Oh. I can't do it for you fully. I can only guide you.

crisp moon
#

Yeah i understand

#

is 0.67% chance of losing 240 times?

near apex
#

probability of losing exactly 240 games + probability of losing exactly 241 games + probability of losing exactly 242 games + ... + probability of losing exactly 10000 games

Here, let's try to compute the first term i.e.
probability of losing exactly 240 games = ?

crisp moon
#

i found it as 0.67%

near apex
#

I don't think that's right.

#

How did you get that ?

crisp moon
#

Yes, it seems like a very high number to me.

crisp moon
near apex
#

Woah. Lol

crisp moon
#

xD

near apex
#

Let's just do it via maths. I haven't computed it myself. So, i can't say if it's that or not with certainty.

crisp moon
#

Isn't the probability of every number between 1 and 10000 equal anyway?

#

like isnt the probabilty of losing 240 times and 241 times equal?

near apex
near apex
crisp moon
#

Oh i didnt know that

near apex
#

Think this way: Let's say you play 4 games.

#

How many ways can you lose exactly one game ?

crisp moon
#

4?

near apex
#

Yes

#

Either you lose the first one, or the second one, or the third one, or the fourth one.

crisp moon
#

I got it

near apex
#

Now, how many ways can you lose exactly two games?

crisp moon
#

2?

#

or 6

near apex
#

It's 6.

crisp moon
#

yes

near apex
#

How are you getting two?

crisp moon
#

it was a misunderstanding nvm

near apex
#

Possibilities of losing exactly two games out of 4:

first and second
First and third
First and fourth
second and third
second and fourth
Third and fourth.

#

Thus 6 ways.

near apex
#

So, we have established that there are different ways of losing 240 games and 241 games. Right?

crisp moon
#

Yeah thanks

near apex
#

Okay. Now, how many ways are there of losing 240 games out of 10000?

crisp moon
#

uhh

#

wait

#

I couldn't find it. is there a formula?

near apex
crisp moon
#

true

near apex
near apex
crisp moon
#

oh yes

#

i got it :

near apex
#

So, basically, losing 240 games out of 10000 is like choosing 240 games out of 10000 which we'll then lose.
So, we need to see how many ways can we choose 240 games out of 10000.

#

Are you familiar with formula for choosing r objects out of n ?

crisp moon
#

formula looks better

near apex
#

Do you know the formula ?

crisp moon
#

no

near apex
#

Okay. Fine.

crisp moon
#

if i took too much of your time i can close the channel then i get help from someone else

#

or later

near apex
#

For, now i'll just tell you the formula. You can watch a video on it later and understand better.

crisp moon
#

haha thanks

near apex
#

So, number of ways of choosing r things out of n is ${n \choose r}$.

#

Damn it.

#

I dunno latex well. Brb

crisp moon
#

Okayy

ocean sealBOT
#

Enemagneto

near apex
#

This should work.

#

Yes

near apex
ocean sealBOT
#

Enemagneto

near apex
#

This is basically the number of ways of choosing r things out of n.

#

@crisp moon Are you familiar with factorials ?

crisp moon
#

No actually im not familiar with complete maths

near apex
#

Umm... It's then almost impossible to do without that. Try watching a video on what factorials are.

#

Also what's number of ways of choosing r things out of n.

crisp moon
#

Ok then, i will save this chat, is there anything more to say about this ?

#

or will this chat help me

near apex
#

There's some more about the probability computation.

#

Okay, let's finish it then.

#

So, for now, we'll assume that number of ways of losing 240 games is some m.

#

Now, let's try to calculate probability of losing 240 games out of 10000 disregarding the order.

#

So, to lose one game - probability is 1/25.
To lose another game at top of that - probability = 1/25 * 1/25 = 1/(25^2)

Similarly for losing 240 games, it'll be 1/(25^240).
However, if exactly 240 are lost so rest 9760 must be won.
So, probability of winning 9760 games = (24/25)^(9760)

Now, probability of exactly losing 24 0 games(disregarding the order) = 1/(25^240) * (24/25)^(9760).

#

Taking the order into account, it is equal to:

$${10000 \choose 240} \cdot \frac{1}{25^{240}} \cdot \left (\frac {24}{25}\right )^{9760}$$

ocean sealBOT
#

Enemagneto

crisp moon
#

woah

near apex
#

Yes

#

Similarly you do for 241, 242, .... upto 10000 and sum all of them.

crisp moon
#

Okay probably i can do with a program, thanks now i can close the channel

#

thank you btw

#

.close

lone heartBOT
#
Channel closed

Closed by @crisp moon

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.

buoyant mirage
#

Doing practice papers for NSAA and I’m stuck on how to do these two questions. The first one I’m not even sure where to start and the second one I think you have to do the next term in the sequence subtract the current one to get an equation which I did but now I’ve got no idea how it’s going to end up as a/3 or a/sqr3

buoyant mirage
#

Close

#

.close

lone heartBOT
#
Channel closed

Closed by @buoyant mirage

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.

quiet lynx
#

This may be an easy question but from the script my professor provided i couldn't figure this out. I need to find the singular points of a curve (0 = f(x,y) so multivariable function) and classify them with the help of the Hessian matrix. I was working on an example, in which i found singular point as 0,0 and the
Hf(0,0) = [2q^2 0, 0 -2]
I of course researched about how to classify them (double points, cusps and hermits?) but somehow I couldnt find how. Could you kindly explain to me what should I do after setting up the Hessian matrix?

lone heartBOT
#

@quiet lynx Has your question been resolved?

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.

dusty wigeon
#

The diagonal light can rotate about the point

dusty wigeon
#

Doing some engineering with cams and a hinge so I want to know how to do this

#

If the parameters of the diagonal was 1

#

At 45° the red line is at 0.5 on the X axis

wispy geyser
#

I can't decrypt what you've written on the paper

dusty wigeon
#

How does the height of follower (RED) correlate with theta

wispy geyser
#

Is it's position on the x axis fixed ?

dusty wigeon
#

The only thing that is moving is the follower up and the diagonal line rotating

wispy geyser
#

Does the follower move horizontaly ? Or Is at a fixed distance from the vertical line on the left

dusty wigeon
#

The follower changes Y axis only

#

The line in red

wispy geyser
#

And what do you want ?

dusty wigeon
#

To know how the height of the follower correlates with the angle of theta

wispy geyser
#

Do you have a length for the red Line ?

dusty wigeon
#

Let me check my 3d model

#

25mm

#

Is it a trigonometry function?

wispy geyser
#

You're problem isn't really clear

#

Yes but to know which one I need to better understand the question

dusty wigeon
#

So with the red follower when it goes up it makes the thing on top rotate as it’s fixed to a point

wispy geyser
#

But in it's initial state the red bar IS on the ground and 25mm in height right ?

dusty wigeon
#

Yea

#

It moves up to rotate

wispy geyser
#

And the diagonal bar IS resting on it AT and angle

#

Ok

dusty wigeon
#

Yea

wispy geyser
#

To solve this you need the difference in x coordinate from the hinge point to where the red bar is

#

This IS a constant because neither one IS moving sideways

dusty wigeon
#

Yea

wispy geyser
#

What do you know in trigonometry ?

dusty wigeon
#

How to use the functions with triangles

#

Soh Cah Toa

wispy geyser
#

Ok then you really need to make a clear drawing of you're problem (see how I needed to Ask a lot of questions to even understand what you were trying to tell me)

dusty wigeon
#

Okay

wispy geyser
#

This should help you have a clear Idea any make a triangle appear on which you Can Do some trigonometry

dusty wigeon
#

Imma simplify this

#

Damn it’s easy to represent but putting it in its simplest form is hard

#

Wait I’m going to stop and try to understand how to represent this

#

So I will come back maybe in an hour

#

Wait I need to kill a spider

#

I killed the spider

#

And I think I have a bit of a better understanding

wispy geyser
#

Here's a nice drawing with :
H : the fixed height of your hinge point
d : the fixed lateral distance between your hinge point and the red bar
L : the fixed length of the bar

and two variables x the height at which the bar is and theta the angle
Now you can see the blue triangle and do trigonometry in that

dusty wigeon
#

Yea

#

Yea that works

#

Okay that answers the question

wispy geyser
#

The key is to do a clear drawing

dusty wigeon
#

Yea

#

What software did you use?

wispy geyser
#

paint

dusty wigeon
#

I drew by hand

wispy geyser
#

but use a sheet of paper that's better

dusty wigeon
#

So yea hopefully I can get a good cam toy

#

For my sister

#

So yea thx again

#

Now time to model

lone heartBOT
#

@dusty wigeon Has your question been resolved?

#
Channel closed

Closed by @dusty wigeon

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.

tulip knoll
#

multiply everything by 21

#

okay

#

let me see real quick

barren yacht
#

im getting 100/21 for some reason

tulip knoll
#

i got 21/31

barren yacht
#

oh hold up

tulip knoll
#

let me try again

#

im close

#

i got 5.8

fervent belfry
#

.

barren yacht
#

u sure its a whole num?

#

do u have the sol?

#

nah bro i checked online too

#

the ans is 109/19

#

its decimal

tulip knoll
#

let me check with a programm i have

#

its supposed to be 5 yeah

barren yacht
#

bro how

#

i did it i got 109/19

shut kayak
#

Do not spam, flood, or post unsolicited advertisements. Do not post responses written by ChatGPT or a similar AI tool.

barren yacht
#

where'd the 3 go?

#

there is supposed to be a 3

#

bro chatgpt is wrong 💀 💀

#

chatgpt high

#

the ans is 109/19

#

where did the 3 go?

#

3(1-3x) = 3 - 9x

#

where the 3 at 💀

#

i did it 3 times u got me trippin

#

chatgpt wrong

#

haha

#

k so

#

dont multiply 21 w everything

#

take the lhs and take 21 as lcm

#

simplify ull get (52 - 23x)/21 = 7 - 2x

#

u can do it later too doesnt matter

#

now take the 21 there and ye multiply

#

look

#

what nah

#

google is dumb

#

hold on leme understand how to type this

#

proly some prof

#

k so

#

look just whatever u typed earlier

#

not everything

#

add a + 3 before the -9x

#

then simplify

#

because 3 (1-3x)

#

equals to 3 - 9x

#

multiply 3 with both terms

#

yes

#

wdym

#

what about the variable

#

"x"

#

ye

#

u write the varible as it is

#

2 into 3x is 6x

#

2x into 3x is 6x^2

#

multiply constants with constants and varibles with varibles

#

only the varible "x" is sqaure

#

because there are 2 "x"

#

bro

#

m into m?

#

yes

#

just an example

#

2m into 3m is 6m^2

#

what grade u in?

#

damn

#

cool

#

im surpsied this hasnt been taugh earlier

#

trust me the q u did is nothing 💀

#

u got me trippin fr

#

i was questioning reality

#

fr bru

#

aint no way i cant do some algebra 😭

#

have u learnt trigno

#

oh

#

the chart?

#

like angles

#

sin 45?

#

bruh

#

cool

#

i really like trigno

#

i doubt you know the basics

#

im trash at teaching literally search 2- (2x+1)/3 + (1-3x)/7 = 7 -2x on google

#

youll find every step easily

#

uh

#

about algebra

#

m^5/m^2

#

??

#

lol

#

what

#

tf u on bro

#

lmfao no

#

bruh imma sleep

#

gn

#

m^5/m^2 = m^5 - m^ 2 = m^5-2 = m^3

#

add me imma talk later

lone heartBOT
#
Channel closed

Closed by @median ledge

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.

barren portal
#

is $e^{-{(x^2+y^2)}}$ and even function of x?

barren portal
#

What I mean by even function of x is to treat y constant

echo socket
#

{-x^2 + y^2}?

echo socket
stray estuary
#

i think they mean $e^{-(x^2 + y^2)}$

ocean sealBOT
#

blanketism

barren portal
echo socket
#

I think it may depend on the way y is bounded

#

Could you show the integral?

barren portal
#

$\int_{-1}^{1} $e^{-(x^2 + y^2)}dx$

ocean sealBOT
#

.doc
Compile Error! Click the errors reaction for more information.
(You may edit your message to recompile.)

echo socket
#

$\int_{-1}^{1} e^{-(x^2 + y^2)}dx$

ocean sealBOT
#

A Lonely Bean

echo socket
#

Yeah sure you can use the property here

barren portal
#

Im in phone little hard

#

but the issues arieses as I have a division by zero

echo socket
#

Where?

barren portal
#

when i find the antiderivative

echo socket
#

Antiderivative of e^(-x^2) is nonelementary though, what do you mean

#

Try differentiating $\frac{e^{-(x^2 + y^2)}}{-2x}$

ocean sealBOT
#

A Lonely Bean

echo socket
#

Does it give you the integrand?

barren portal
#

That’s what i wrote

#

hold on

#

ahhh

#

let u= x^2+y^2

echo socket
#

Yeah, you can simple divide by the derivative of the inside only when the derivative is constant

barren portal
#

That’s what i meant

keen plinth
#

are you xy probleming here

#

like this integral is very suspicious

#

where did you even get it from

echo socket
#

Yeah I don't think you would be asked to evaluate that

barren portal
#

Why do you think it’s non elementary?

keen plinth
#

this is a well known result

barren portal
#

I can use substitution right?

naive valley
#

it's not elementary, in the sense that people had to define a function for it, namely the error function

barren portal
#

notice im differentating with fixed y

naive valley
#

but the error function is widely available in software and its properties are well known, so it's not really any worse to deal with than say sin or cos

barren portal
#

partial integral it is

naive valley
#

if you express the exponential as a product, you can pull the y part out as it's a contant with respect to the integral

keen plinth
#

why do you need this integral

barren portal
#

I just want to do this

keen plinth
#

this doesn't have a good answer

barren portal
#

thought to use even function property

keen plinth
#

well in 2 dimensions you want to respect the circular symmetry

barren portal
#

but hit the wall

keen plinth
#

but you've made the domain of integration a square

#

so you're gonna have a hard time doing it by hand

barren portal
#

I don’t think its hard to do

#

maybe change order of integration?

keen plinth
#

,w integral -1 to 1 integral -1 to 1 exp(-x^2 - y^2) dx dy

keen plinth
#

erf is defined as the antiderivative of e^(-x^2) with some scaling factors

barren portal
#

Its non elementary double integral ig

#

what suprises me, is the inner integral is possible when limits are -1 to 1 but not when 0 to 1

keen plinth
#

no none of your integrals are elementary

#

,w integral -1 to 1 exp(-x^2 - y^2) dx

barren portal
#

I commited some mistakes while substitution

#

my bad

lone heartBOT
#

@barren portal 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.

undone ledge
lone heartBOT
undone ledge
#

what should be the aproach to this question

#

im stuck

#

also in the last step
the equal has 18

fallen verge
#

You can do change of base with log base 2

#

I think that would be better

undone ledge
#

hm?

tardy stag
#

instead of doing ln do log2

undone ledge
#

oh?

#

alright i will try that

#

1 sec

#

Damn

#

thats it right?

#

so option (b)?

#

yeah cool got it
thanks

#

.close

lone heartBOT
#
Channel closed

Closed by @undone ledge

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.

undone ledge
#

i dont know how to start this question

lone heartBOT
lethal belfry
#

express everythng either in terms of anglea

#

for $instance cos2x=1-2sin^2(x)$

ocean sealBOT
#

physicsrocks

undone ledge
#

hmm..

#

not ringing a bell

#

whats anglea

mystic vortex
#

I believe they mean angles

lethal belfry
#

yeah, my bad, sorry

undone ledge
#

oh

#

like the lhr or rhs

lethal belfry
#

LHS,if possible

undone ledge
#

ok i will try..

lethal belfry
#

I'm jus thorwing ideas that may work, I've not tried it myself

undone ledge
#

understandable

mystic vortex
#

Is the implication there that the equation is true for all values of a?

lethal belfry
mystic vortex
#

Hmm ok

#

I've never seen a problem like this but I'd agree trig identities seems like a good first step

#

Also, are k, w, and p all supposed to be integers?

undone ledge
mystic vortex
#

Cause it talks about factors, but it doesn't explicitly say

undone ledge
#

that did help

#

hmm

lethal belfry
undone ledge
#

oh i multiplied and divided 4 to the whole equation

#

to use it in identity

lethal belfry
#

ah,ok

undone ledge
#

2cos a . sin a = sin 2a

lone heartBOT
#

@undone ledge Has your question been resolved?

undone ledge
#

ahhhh got it

#

.close

lone heartBOT
#
Channel closed

Closed by @undone ledge

Use .reopen if this was a mistake.

undone ledge
#

thanks

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.

undone ledge
lone heartBOT
undone ledge
#

what should be the aproach

#

oh wait .. i just got it.

#

smh sorry

#

.close

lone heartBOT
#
Channel closed

Closed by @undone ledge

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
#

how does this simplify to this

lone heartBOT
minor needle
#

it's like

#

an apple minus half an apple

#

To visualize

alpine sable
#

1-0.5

#

in my mind it should be 0

#

but it clearly isnt

ocean sealBOT
alpine sable
#

i suppose that makes sense

#

x-x/2 and if lets say x=5 then:
5-5/2= 5-2.5=2.5

#

5/2 = 2.5

minor needle
#

yes, but

#

this is how it works, I mean for every x, even for the expression like -voy^2/g

alpine sable
#

well

#

is is the same if what we talk about is constant

#

5, 20, (17/200)^2 or -vy^2/g

#

or so i suppose

lone heartBOT
#

@alpine sable Has your question been resolved?

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.

lavish kelp
#

I am confused on how they got the maximum value

lavish kelp
#

I know for the minimum value, they just took the vertex

#

but how did they get the maximum value mathimatically

#

because it does not give me a graph

near garden
#

if the part of the graph given doesnt contain the vertex it would be the lower end of the arch

#

you just have the range of y value as the lower y of it and the upper y of it

#

however if the vertex is included only one side of the arch can be the maximum (or both be)

#

taking the coefficient of the squared term as positive that is

lavish kelp
#

so the maximum value is just the 2^2?

near garden
#

what

lavish kelp
#

I am as confused as you are

#

how did they get the numbers 4 and 6 for the maximum mathematically

near garden
#

or just take the two end points of the graph, plus the vertex if it's included in the range, and the lowest y and highest y would be the y bound over the range

lavish kelp
#

I am not given coordinates

near garden
near garden
lavish kelp
#

ok so

#

what I do

#

is

#

wait what

near garden
#

huh

lavish kelp
#

im not given any numbers on my graph

near garden
#

wdym

lavish kelp
#

its just a raw graph with a parabola

near garden
#

how would you ahve the graph if you dont have the numbers

#

and the graph is drawn with the information given

#

both the formula for the function and the range

#

for you to find the y range

lavish kelp
#

let me take a photo

near garden
#

ok

lavish kelp
#

So I already know the minimum value is -5, x=3

near garden
#

yeah and?

lavish kelp
#

I have no clue on how to get the maximum value

near garden
#

from the minimum value of a quadratic, either going to the left or to the right the value should always be increasing if the coefficient of the squared term is positive

#

so the maximum value can only be at one end of the x range or the other, given that the x range crosses the vertex of the quadratic function

lavish kelp
#

the squared term is positive

near garden
#

yes

#

so you can just plug in the two ends of the x range into the original function to see which one is higher and that would be the value for the y maximum

lavish kelp
#

oh wait

#

So I plug in 0 or 5, which ever give me the highest outcome is my maximum

near garden
#

yes

#

and drawing out the function on the graph would probably help

lavish kelp
#

x = 0, 4 is my maximum then

#

bc 0 gives me the highest outcome

near garden
#

mhm

lavish kelp
#

this helped

#

tysm

near garden
#

and also you can look for which ever end is farther from the vertex

#

since quadratic graphs are symmetrical around the vertex vertical line and the farther end point from the vertex woulda grown higher

near garden
lavish kelp
#

wait this makes way more sense

near garden
near garden
#

it works

lavish kelp
#

wait thats cool

near garden
#

:)

lavish kelp
#

thank you for making math math

near garden
#

XD np

near garden
#

but thats not to be worried about for now

#

hf wiht math

lavish kelp
#

I gotta worry about that next year 💀

near garden
#

XD

lavish kelp
#

full IB

near garden
#

what year are u in

lavish kelp
#

going into 10

near garden
#

sameeeee

lavish kelp
#

nicee

near garden
#

i took ap calc ab last year

#

well technically april/may i forgot this year

#

may

lavish kelp
#

thats cool

near garden
#

mhm

#

welp gl with that

lavish kelp
#

enjoy the rest of your day :)

near garden
#

u2 <3

lavish kelp
#

.close

lone heartBOT
#
Channel closed

Closed by @lavish kelp

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.

buoyant mirage
#

Doing practice papers for NSAA and I’m stuck on how to do these two questions. The first one I’m not even sure where to start and the second one I think you have to do the next term in the sequence subtract the current one to get an equation which I did but now I’ve got no idea how it’s going to end up as a/3 or a/sqr3

lone heartBOT
#

@buoyant mirage Has your question been resolved?

buoyant mirage
#

No

full helm
# buoyant mirage No

hi. what happens if the function starts decreasing within the small interval you’ve given it?

#

for the second one that is

#

you’ve said, well, the function increases if f(x+1)-f(x)>0, which is somewhat going in the right direction, but it leaves room for error

#

if you’re allowed to use calculus, it becomes trivial. Think of the derivative

#

now for the first one. try to establish a relationship between L and m, and p and M. Then you can try applying the fact that LM is 5 units long

buoyant mirage
#

Ok thanks!

#

Thanks I got the second one now

#

Why is great than or equal though and not just greater than?

full helm
buoyant mirage
#

Weird

full helm
#

funny thing, I once got into a (verbal) fight with a teacher regarding exactly this

buoyant mirage
#

How?

full helm
#

in the exam he asked a question which asked for the exact same thing that you’ve been asked (different numbers)

#

It was a mcq. One of the choices included the endpoints, and the others didn’t. I picked the one that didn’t, and he claimed I was wrong

#

and I was extremely salty, it was the only question I got wrong. I took it up with him because he never set a definition for increasing properly in class

it doesn’t make sense for something to be increasing when it literally doesn’t increase or decrease at all at that point (f’=0) (to me, as I mention below, different people have different definitions)

#

but yeah

#

different book/curriculums/teachers have different definitions

#

it’s good this mcq you have doesn’t include both the endpoint included/not included though. Doesn’t leave room for questioning

#

anyways, I digress

#

Have you thought of a way for the first one

lone heartBOT
#

@buoyant mirage Has your question been resolved?

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.

proper vine
#

What are the key features of radical functions

proper vine
#

Im not sure what they are

#

like if there is a domain, range

#

asymptote

#

max min

#

mud please man

#

you got this

#

help

celest terrace
proper vine
#

yes im aware

#

im looking for things like this

celest terrace
#

take the square root of x for example

proper vine
#

This is an example

celest terrace
#

sure

proper vine
#

but for quadratic

celest terrace
#

which isn't a radical function

proper vine
#

ya

#

mm so im not looking for something similiar

celest terrace
#

not really

proper vine
#

So what would be the awnser for this

celest terrace
#

what's the radical function?

proper vine
#

Its a general like

#

there isnt really

#

this is the example given by the teacher

celest terrace
#

can you take a picture of the entire question?

proper vine
#

ya

#

sure

#

this is like the

#

describtion

celest terrace
#

ok

proper vine
#

Task Goal: To demonstrate your knowledge of the functions you have investigated in this course.

Throughout this course, you have looked at the key features of a variety of functions, including quadratic functions, radical functions, reciprocal functions, exponential functions, and sinusoidal functions.

In this task, you will be demonstrating your knowledge of each of these functions by completing this Functions template. Make a copy and once completed, download the files as a PDF.

Complete the template for each functions using the linear function y=mx+b as a model.

celest terrace
#

so basically, function, representations, key features, and description?

proper vine
#

ya

#

you can see here

celest terrace
#

have you seen what a radical function looks like?

proper vine
#

ya

#

I have diagrams for it

celest terrace
#

mind showing them?

proper vine
#

Here

celest terrace
#

so, what are you confused about?

proper vine
#

what are the key features

celest terrace
#

there's always going to be a domain and range for a function

proper vine
#

ya im aware

#

so Domain can be all real numbers

celest terrace
#

no

proper vine
#

if it is bigger than zero

celest terrace
#

almost

#

bigger or equal to zero

proper vine
#

oh alright

#

is that always the case?

celest terrace
#

if the root is an even number

#

for odd roots, it's all real numbers

proper vine
#

ya

#

but there is no root for 0

#

is there

#

its going to be

#

n/a

celest terrace
#

for 0?

proper vine
#

ya

celest terrace
#

like x^0?

proper vine
#

you said x can be zero

#

arent we talking about radical

celest terrace
#

we are

#

x can be zero

proper vine
celest terrace
proper vine
#

ya your right

#

mb

#

0 is 0

celest terrace
#

a zeroth root is not defined

proper vine
#

yep

celest terrace
#

the range depends on costant c right?

#

since it moves the graph up and down

#

so it's also limited

proper vine
#

Ya so how can I explain

#

that

#

without using actual values

celest terrace
#

so here's an example

#

a is positive

#

c is 1

#

b is 0

#

can you tell the range?

proper vine
#

xer

#

x is equal to bigger than 1

#

or mb

celest terrace
#

y

proper vine
#

yer

#

y is equal to bigger than 1

celest terrace
#

yes

#

so that's the range

proper vine
#

Okay I can explain that

#

so whats next

celest terrace
#

if a is negative though

#

what's the range for this one?

proper vine
#

yer with the restrcition of y bieng smaller or equal to 1

celest terrace
#

yes

#

so if a is positive, the range is greater than or equal to c, right?

proper vine
#

ya

#

and if its negative

#

its vise versa

celest terrace
#

yes

#

now for domain

#

which variables affect the domain directly?

proper vine
#

d

#

(x-d)

celest terrace
#

yes

proper vine
#

x+d

celest terrace
#

domain for this?

proper vine
#

xer

#

restrcition

#

is x has to be larger or equal to negative 3

celest terrace
#

yes

proper vine
#

I just finished writing it down

#

so what is there

#

besides

#

domain and range

celest terrace
#

just one more thing: the domain also depends on the sign of x

#

so besides domain and range...

proper vine
#

yep

celest terrace
proper vine
#

?

celest terrace
#

there's only a domain and range restriction for even numbered roots

proper vine
#

alright

#

so what other key feature are these

#

besides

#

domain and range

celest terrace
#

i guess the index?

#

the number next to the check mark

proper vine
#

mm

#

a

#

or k

celest terrace
#

more like this

proper vine
#

oh

#

mmm how do we cover this

celest terrace
#

hm

#

you know how a radical can be rewritten into the radicand and a fractional exponent?

proper vine
#

ya

wheat isle
proper vine
wheat isle
#

just x>=-3 works

celest terrace
#

^

wheat isle
#

because xER implies the domain exists for all real numbers of x

proper vine
#

Can it sometimes be xER

#

or no

celest terrace
#

oh it isn't

proper vine
#

so no

#

?

celest terrace
#

nope

wheat isle
proper vine
#

no just if this can be xer

#

like a radical can

celest terrace
#

a radical can't ever be xer

proper vine
#

would that apply to range

#

or no

#

yer

celest terrace
#

it would

proper vine
#

so there is no yER

celest terrace
#

nope

#

,wolf graph sqrt(x)

ocean sealBOT
celest terrace
#

you can see how the domain doesn't exist when x is negative

#

since the function doesn't exist there

proper vine
#

alright

#

I fixed it

#

Do we have any more key feature or can we move to the reciprocal functions?

celest terrace
#

i can't think of any more you can put...

proper vine
#

thats fine

#

lets move on

celest terrace
#

alright

proper vine
#

Reciprocal

#

i know it has asymptote

#

and domain and range

#

thats all i can name

celest terrace
#

yes

proper vine
#

the asymptote is depended on the c constant

#

Correct

celest terrace
#

which asymptotate are you talking about?

#

the vertical or the horizontal asymptote

#

just specify that

proper vine
#

y=

#

so horizontal?

celest terrace
#

yes

wheat isle
#

Btw just a thing to note that reciprocal functions also have the domain where x cannot be 0

celest terrace
#

for this graph, x could be zero

wheat isle
#

True

celest terrace
#

i think you're saying how k can't be 0?

#

so the denominator cannot be 0

wheat isle
#

I’m just thinking of the form 1/x where you cannot divide by 0

celest terrace
#

ah yes

proper vine
#

Asymptote- A reciprocal function has an asymptote meaning that there is a restriction that the line will never reach a certain number.
Horizontal asymptote - The horizontal asymptote depends on the value of c since the value of c is the horizontal asympotote.

#

This is what I wrote so far

celest terrace
#

that's fine

#

for the vertical one, what variable is that?

proper vine
#

c?

celest terrace
#

no

#

c is the horizontal asymptote

proper vine
#

ya

celest terrace
#

which variable shifts the graph left and right?

proper vine
#

mb

#

i thought you said what variable is that

celest terrace
#

ah

proper vine
#

the verticle one depend on the d value

celest terrace
#

yes

#

so then the asymptote is x = d

proper vine
#

ya

#

Vertical asymptote - The vertical asymptote depends on the value of d since the value of d is the vertical asymptote.

celest terrace
#

the value of x = d

proper vine
#

ya

celest terrace
#

basically just say

#

the vertical asymptote is a line where x = d

#

and the horizontal asymptote is a line where y = c

#

just a suggestion though, i'm not sure how your teacher would want it

proper vine
#

I wrote it anyway

#

now on to domain and range

celest terrace
#

let's start on domain

#

the x values

#

for the domain

#

x exists everywhere except for one value

proper vine
#

So xer with a restriction

celest terrace
#

kinda yeah

#

you could say

#

xER except when x = d right?

proper vine
#

ya

celest terrace
#

since the only restrictions are the asymptotes

proper vine
#

yep

celest terrace
#

same could be said for the range and the horizontal asymptote

proper vine
#

Cant I just write this

#

Domain: X can be all real numbers beside the value of the horizontal asymptote.

#

Range: y can be all real numbers beside the value of the vertical asymptote.

celest terrace
#

that works

proper vine
#

Is that all

celest terrace
#

instead of saying beside, try saying except

celest terrace
proper vine
#

alright

#

now we can move the the final thing

celest terrace
#

ok

proper vine
#

Exponential Function

#

this seems easier

celest terrace
#

it should be

proper vine
#

yep so domain

#

and range will be pretty similiar to the radical one

#

just vise versa

#

right

celest terrace
#

a little

#

are there any restrictions?

proper vine
#

dosent seem like it

#

I might be wrong

#

but

celest terrace
#

but?

proper vine
#

oh there

#

is

#

nvm

#

ok

#

so depending on

#

the c variable

#

say 1

#

for an example

celest terrace
#

okay

proper vine
#

it will make x always one

#

wait thats false

#

mb

celest terrace
#

???