#help-0

1 messages · Page 180 of 1

stone garden
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I think i dont know what i think...

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Do we need maybe the p-q formula now?

pseudo ice
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Not really

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If the one I’m thinking of is what you mean

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There’s one obvious solution here

stone garden
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Do i need to calculate them first?

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Oh no wiaat

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I think i know i must write only 0,01x^3 - 0,3^2 + 2,25x = 0 and i need to say that it starts from zero in a sentence in the text idk

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And then i need to calculate it first? Or

pseudo ice
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What do you mean by “it starts from zero”? I think you’re saying what I wanted you to say(!)

stone garden
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I think that the calculate zeros start's from zero because we start there and when we have for example -5 it procceds to start before i think

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Hmmmm

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I don't know

pseudo ice
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Alright for a moment forget the whole question

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Let’s say I give you y^2 + 5y + 4 = 0, could you find what y could be for me?

stone garden
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I think y is the time in minutes

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Do i need to write it in minutes??

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Hmmm

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Is it then 2y^1 + 5y?

pseudo ice
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No no noooooo

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Ignore everything else, like the whole question and everything

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Here y isn’t time or anything, it’s just a quadratic equation

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,w solve y^2 + 5y + 4 = 0

stone garden
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Hmm how do we find that we have -1 and -4?

pseudo ice
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You can for example factor it as y^2 + 5y + 4 = (y+4)(y+1)

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Or you can use the quadratic formula

stone garden
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I think i know now because y is 1 bc there is y and so we need ^2 and make it ^1 and 1 is then left so it is plus i made the plus to minus and then the 4 i do the same and then its -4

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But why especially the -4 can i say -5y too?

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I don't understand rip

pseudo ice
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Also I have to go and get a bit of sleep sadcatsadcatsadcat

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May be back later but if I don't see you then, hopefully I'll catch you around catLove

stone garden
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Oki

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Good night 🌼

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Thanks you still helped me a bit to understand it more😌🌼

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See you around🌼

pseudo ice
lone heartBOT
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@stone garden Has your question been resolved?

lone heartBOT
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tawny sonnet
lone heartBOT
tawny sonnet
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I’m not sure where to start graphing this ik that it’s an exponential function

strong compass
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It’s a polynomial, exponentials are when x is in the power

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Do you know what I mean when I say the roots of the equation?

tawny sonnet
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Would it be the entire equations squat root

strong compass
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Not quite, it’s when x^ -9= 0

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You need to know what x values make that true

tawny sonnet
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3^2=9

strong compass
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Nice so 3 is a root

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Do you know another root

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Hint ||the sqrt(a^2) = +a and -a||

tawny sonnet
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Hmmm I’m not sure is there another squat root that equal 9

strong compass
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Are you aware there are 2 solutions to a square root?

tawny sonnet
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Ohhh yeah because -2x-2 is 4

strong compass
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There is only one type of square root, but let’s say for another example I have x^2 = 4

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Of course one solutions is 2

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But -2 is also a solution

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Because -2 * -2 = 4 (because -1*-1= 1)

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Exactly

tawny sonnet
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Yeah

strong compass
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So given that what’s the other solution

tawny sonnet
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-3^2

strong compass
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So x = 3 or x= -3

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Do you know how to factorise it from here

tawny sonnet
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Hmm I’m not sure

strong compass
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Nvm then, so you know when x = 3, y= 0 and when x = -3, y=0

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If you wanna plot those on your axis

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We can begin to work out the points that this curve goes through

tawny sonnet
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Ohh ok I think I’m starting to get it

strong compass
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That’s good

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So we need 3 points to work out how we should draw this, we have when y=0, any idea what we should try find next?

tawny sonnet
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Would you take a random x point in either direction and plug it into the formula

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?

strong compass
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You could, but that might be a bit of a pain to work out

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What happens if I put x= 0

tawny sonnet
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Would it be y=9

strong compass
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Yep

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Oh wait not 9

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Y= x^2 -9

tawny sonnet
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-9?

strong compass
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Yeh -9

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So you know if goes through those points, now you jusy need to sketch a smooth ish line through those

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Does that make sense to you?

tawny sonnet
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Just to recap when x=-3 y=0 and when x=0 y=-9 and x=3 y=0

strong compass
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Yeh

tawny sonnet
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How did you know to flip the sighns on the equation ?

strong compass
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What do you mean?

tawny sonnet
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The original equation called for f(x)=-x^2+9

strong compass
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My miss read sorry, it’s the same roots but you were correct earlier x= 0, y=9

tawny sonnet
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Ok I think that clears things up

strong compass
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It’s the same roots because 0 = -x^2+9
Adding x^2 to both sides: x^2=9

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Does that make sense now

tawny sonnet
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Yeah

strong compass
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Ok good

tawny sonnet
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Thank you

strong compass
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For a short cut, it might be worth knowing, this type of quadratic is called a “difference of 2 squares” as you get comfier your might be able to recognise these and jump straight to the solution, it’s whenever you can write something as y=(x+a)(x-a) where a is a number, it means that there is no x term, just y=x^2-a^2

tawny sonnet
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Yeah

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.close

lone heartBOT
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queen bear
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can someone help me figure out the rest of this problem?

queen bear
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having trouble with D

placid zinc
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a and c are right, but d is wrong?

queen bear
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how so

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i meant d second part and e

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im not sure how to progress

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@placid zinc

placid zinc
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Basically this is a first order linear DE. There's a whole solution method to them you'll be tested on. Give that page a skim.

queen bear
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will do, would you happen to know the answers to the ones i am missing so i can check the work?

placid zinc
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If you just want answers, check out Wolfram Alpha, which can generate answers to basically anything for you

queen bear
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for the same topic?

placid zinc
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Easy in-browser math engine

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Can do differential equations, yeah

queen bear
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cool thanks for the help!

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i didnt use the wolfram but i did end up getting 2.33 for final answer

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the link you sent earlier helped actually, will have to check out more of their stuff

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pulsar bane
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Hello, this may look like a dumb question but its 4 am and yeah... Ok so why's the first one wrong but the second one is correct (the 2 identities on the right)

gusty gorge
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how are both of these correct?

lone heartBOT
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@pulsar bane Has your question been resolved?

pulsar bane
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but the second one is

pulsar bane
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and why's the second one correct

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idk why the first one that i did is wrong

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Oh god I'm stupid and sleep deprived, he moved the tan cuz you cant do the other stupid thing that i did

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Nvm I'm sorry 🤣

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low zephyr
lone heartBOT
low zephyr
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can i get a step by step on what to do for these types of problems ?

lone heartBOT
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@low zephyr Has your question been resolved?

lone heartBOT
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@low zephyr Has your question been resolved?

lone heartBOT
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@low zephyr Has your question been resolved?

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alpine sable
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14048

lone heartBOT
alpine sable
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How would I round that to 3 sig figs?

tight locust
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depends on context

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you can't just have sig figs in isolation

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it depends on the accuracy of your measurement

alpine sable
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101115.65401744

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then I used this number to calculate return of investment

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and got 14048

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Teacher requires 3 sig figs... so I have no clue how to round this

lone heartBOT
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@alpine sable Has your question been resolved?

alpine sable
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.close

lone heartBOT
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ocean sealBOT
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AwitNamanSayoPar

stone plaza
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??

last ether
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What about that

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Solve for x?

stone plaza
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its is x = -1,1

last ether
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Take the square root of both sides

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Yeah

lone heartBOT
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stone plaza
ocean sealBOT
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AwitNamanSayoPar

stone plaza
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help

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is the answer x = 1,-1 😭

ocean sealBOT
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Stephen

long axle
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Try squaring those and see what u get

stone plaza
ocean sealBOT
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AwitNamanSayoPar

stone plaza
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wrong?

long axle
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Yea correct lol I literally just said that

stone plaza
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ah ok

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thank you

long axle
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Np

lone heartBOT
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last ether
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i has cyclical properties that makes your solution incorrect

last ether
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Shit

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.close

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long axle
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Wait what @last ether

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i is wrong?

last ether
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No, -i is wrong @long axle

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i is correct

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They had x = +- i

wary stream
last ether
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No

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It was bad timing

long axle
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But if u square -i don’t u get -1?

last ether
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No

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You get 1

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I'm pretty sure

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Am I being dumb

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Yeah no (-i)^2 = -1

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I'm not being dumb

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Oh wait

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I'm going to throw a fit

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LOL

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DID I JSUT THINK 1 = -1

long axle
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$(-i)^2 = (-1)^2 \cdot (i)^2$

last ether
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I'm done

ocean sealBOT
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Stephen

last ether
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Naw naw naw I'm done

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I just thought -1 = 1

long axle
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Lol rip

last ether
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Nah bro G I'm resigning

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I can't just correctly do a Riemann summation and then do this shit

long axle
last ether
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Screenshotting this

long axle
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Lol

fallen verge
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.coose

modern sedge
fallen verge
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no

lone heartBOT
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high wolf
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Could someone help me solve this using partial fractions:

modern sedge
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I gtg soon, so I wont help you with the partial fractions, but I would start by factoring out 3 and moving it out of integral

high wolf
modern sedge
high wolf
lone heartBOT
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@high wolf Has your question been resolved?

slate monolith
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you can already find the integral of 3/x-2

high wolf
slate monolith
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for the second part yeah

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pfd is for a single fraction usually

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the first fraction though is really simple

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seperate into two integrals

lone heartBOT
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@high wolf Has your question been resolved?

high wolf
slate monolith
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you have two fractions

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make those two integral

lone heartBOT
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@high wolf Has your question been resolved?

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vale kayak
#

To prove if a function is discontinuous at a certain point using epsilon-delta definition; what if i showed that |f(x) - f(c)| is less than some number, hence not true for all epsilon > 0, hence limit does not exist at c?

mortal trellis
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do you mean bigger than some number?

vale kayak
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i can only show its less,
take f(x) = x+1, and f(1)=0
then |f -f(1)| = |x+1| for some |x-1|<delta

mortal trellis
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less doesnt show anything

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either less than all epsilon or bigger than one epsilon

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less than one epsilon doesnt give anything

vale kayak
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then how do i go about proving the discontinuity?

gusty gorge
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wait what

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oh I see

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you basically show that there exists an epsilon such that you can't find the delta

vale kayak
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f(x):= 0 when 0<=x<=1
x+1 when 1<x<=2
i have to show its discontinuous at x=1

gusty gorge
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in this case, epsilon = 0.5 works fine

vale kayak
gusty gorge
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huh?

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epsilon-delta definition of continuity at c is that for all epsilon > 0, you can find a delta such that |f(x) - f(c)| < epsilon for all x within delta of c

vale kayak
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yes

gusty gorge
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suppose you say epsilon = 0.5

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now show that |f(x) - f(c)| has to be greater than 0.5, no matter how small you make delta

vale kayak
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got it, thx

lone heartBOT
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glossy shuttle
#

I don’t understand where it says “when two terms do not have any common factor except 1. Can someone please explain that to me?

stray bloom
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those would be co-prime numbers

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for example, 3 and 4 are co-prime, 2 and 6 are not (both even)

lethal belfry
glossy shuttle
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Okay. So how would I know exactly when to divide and multiply? I’m doing these problems and I’m answering them correctly but I think I’m just getting lucky because I don’t know when to multiply or divide.

stray bloom
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in those cases you need to perform the "rule of 3" i think it's called

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yeah, direct rule of 3

glossy shuttle
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Okay thank you.

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.close

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stray bloom
#

I'm looking for information on how to construct an ellipse given 5 points of it, graphically, I've seen a way or two but I don't know whether the way I found has a name, is documented, or is novel

stray bloom
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In my case I start with 4 points and draw the regions where there can be a center of an ellipse that could pass through them, repeat that for all combinations of 4 out of 5 points and it should give 1 unique point or none if the shape is concave

lone heartBOT
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@stray bloom Has your question been resolved?

lone heartBOT
#

@stray bloom Has your question been resolved?

prime crown
stray bloom
#

🤷‍♂️

limpid spade
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jesus what

stray bloom
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It's a bit obtuse

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basically drawing parallel lines and middle points of segments

lone heartBOT
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@stray bloom Has your question been resolved?

lone heartBOT
#

@stray bloom Has your question been resolved?

heady cargo
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Hello>>

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Hello??

stray bloom
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yeah

alpine sable
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Ax+b = 0 correct yes?

stray bloom
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please use other channels

alpine sable
#

?

stray bloom
lone heartBOT
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@stray bloom Has your question been resolved?

slate monolith
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@stray bloomI'm guessing this is your own experimentation?

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idk if you'll find someone here

stray bloom
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correct

slate monolith
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there might not be a solution

stray bloom
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my guess is that those blue regions on the picture are the regions where you can put a center, starting with 2 points it's most of the plane, with 3 you can discard more, and then with 4 and 5, it should leave a single point or none

slate monolith
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yeah I have no idea

stray bloom
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maybe i should try to learn how to use the 3b1b software

slate monolith
#

thats just for visualization

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not sure how that would help

stray bloom
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at least for explaining the method

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where could i find researchers that respond to messages?

slate monolith
stray bloom
#

would this be algebraic geometry?

slate monolith
#

what year are you even

stray bloom
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i'm not studying, i've done baccaulaureate about 3 years ago

karmic rapids
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this does not belong in the advanced channels

slate monolith
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this person has already finished their bachelors

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i think that is worthy of advanced

karmic rapids
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what? just because someone has X degree doesn't mean every question they ask is on that level

slate monolith
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I didnt say a research level

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early uni is part of advanced

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just not here

karmic rapids
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there's an early uni section

slate monolith
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yeah but I thought that was unlocked when you got advanced access

karmic rapids
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also this is far from being algebraic geometry

slate monolith
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what is it then

stray bloom
#

I honestly don't even know the definition

karmic rapids
#

alg geo is like

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doing geometry with algebraic means

slate monolith
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well yeah

karmic rapids
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like comm alg

slate monolith
#

geo-trig is not enough

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this is not something a highschooler can do

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at least not a highschooler learning geo/trig

karmic rapids
#

geo trig is not only for high schoolers

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this question belongs there

slate monolith
#

alr

formal glade
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.close

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u should do dat bc this is unused

slate monolith
#

.close

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serene mirage
#

hey

lone heartBOT
serene mirage
#

\int (x)/(cos^(2)4x)dx

last ether
#

Use tabular method for IBP

serene mirage
last ether
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Hm

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Yeah I'd still use tabular/IBP

serene mirage
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the x in the numerator threw me off

last ether
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Well that's the same as integrating x • sec^2(4x)

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Which is easy to do IBP/tabular on

serene mirage
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oh wait

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we got sec cause 1/cos

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does the x act like a 1

last ether
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Wdym does the x like a 1

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No I just simply rewrote the integrand

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x/cos^2(4x) = x • 1/cos^2(4x)

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The x "doesn't act like a 1", that wouldn't make sense

serene mirage
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ok

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sorry it took me a while to process this i see now

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so u = x and dv = sec^2 4x @last ether

last ether
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Sure

serene mirage
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would my answer be

last ether
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Lemme check

last ether
serene mirage
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alright thanks

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.close

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naive python
#

Hey, can someone help me with geometric calculations?

naive python
#

Can u help me find the area of 5?

naive python
slate monolith
#

nah

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idk what is this lol

naive python
#

<@&286206848099549185>

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naive python
#

Sorry, I am kinda in a time crunch

#

<@&286206848099549185> now it has been 15 mins

#

I found another side length btw

#

Please help y’all

#

<@&286206848099549185> I highkey need to keep spamming

#

Desperation rizz — pleaseeee

lone heartBOT
#

@naive python Has your question been resolved?

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#

@naive python Has your question been resolved?

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cerulean goblet
#

Hey i’m relatively new to advanced maths and just wanted an easy way to estimate what a cubic equation would look like on a graph.

cerulean goblet
#

For example, a quadratic equation is easy to visualise

slate monolith
#

,w graph x^3

ocean sealBOT
cerulean goblet
slate monolith
#

its the same thing as any function

#

plug in some x values

limpid turret
#

There are different kinds of cubics

slate monolith
#

trace it out

cerulean goblet
#

Oh, that makes sense

limpid turret
#

,w plot y=x^3-x

worn fox
#

You should play around on desmos with sliders for the coefficients to see how they affect the shape of the graph

naive valley
#

you can make a few general observations

#

when x is large, in one direction the function must go to +infty and in the other direction it must go to -infty

naive valley
#

there can be at most 3 real roots

#

etc

cerulean goblet
#

alrighty! Thank you everyone for the help!!

#

.close

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junior warren
lone heartBOT
junior warren
#

how to go about solving this?

#

tried this didnt work

surreal meadow
#

you’re assuming the two ns are equal, they are not

junior warren
#

so two variables/

surreal meadow
#

i would list the values that are 3 mod 4 and 5 mod 7

#

and find the one that is in both

junior warren
#

would this process work?

#

actually i can really isolate for m or n

#

so probably not?

surreal meadow
#

you can’t solve for n and m with just one equation

#

i would do what i said above

junior warren
#

oh since the 3 and 5 is the remainder

#

which gets placed in front of the modulus?

surreal meadow
#

i would start with the mod 7 values and then go to the mod 4s, since there’s less mod 7 values

#

ok i seem to have misunderstood

#

actually no

#

i believe you are solving for a = 3 mod 4 and a = 5 mod 7

#

so i would list the numbers between 0 and 27 with remainder 5 when divided by 7

#

and then do the same with the values with remainder 3 when divided by 4, until you find a match

junior warren
#

oh ok, so theres no set algebraic way to solve it?

#

moreso just guess and check

surreal meadow
#

not that i’m aware of

#

but i’m not too well versed in this so there could be

junior warren
#

yeah i tried an algebraic solution but got 3mod4 congruent to 2

#

which it just isnt

#

so its 13?

worn fox
#

13 is not congruent to 3 mod 4 unfortunately

junior warren
#

hm

#

even though it has r5 when /7 and r3 when /4

#

isnt that what i am looking for?

#

i dont think it has to be congruent

#

it is asking for the number before the mod i think?

#

maybe i am wrong

worn fox
#

13 does not have remainder 3 when divided by 4

junior warren
#

it has r1

#

yeah

#

let me try agian

#

i believe 19?

worn fox
#

19 yes

junior warren
#

19 r5 /7 and r3/4

#

and lowest

#

ok i see the pattern

#

however in a next one i have same idea

#

but no number in common. ):

worn fox
#

Youre missing a number in each list

#

(Which necessarily will be the answer)

junior warren
#

possibly 1?

worn fox
#

Yes

junior warren
#

since 1=0/4 +1

worn fox
#

That's 1 more than a multiple of 4 and a multiple of 7 yes

junior warren
#

ok i didnt know i had to do that first one

#

i see

#

ok that makes sense

#

so quick example if i needed remainder 0

#

its all perfect multiples

#

AND 0

worn fox
#

And zero yes

junior warren
#

ok thank you

#

got all of them right

#

appreciate it

#

.close

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#
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flat vale
#

how to do 💀

lone heartBOT
flat vale
#

idk how to start

lone heartBOT
#

@flat vale Has your question been resolved?

worn fox
#

Assume a is not zero wlog

#

What can you do to the equation ab = 0 to conclude that b = 0

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lavish cedar
lone heartBOT
alpine sable
#

Can someone define functions in simple terms

lavish cedar
#

sikeman this is my box?

#

could you go into a free one

#

please

#

thanks

#

just probobility

#

proabiltiy

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#

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lavish cedar
#

.close

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serene mirage
lone heartBOT
molten pivot
#

factor out 16 inside the radicand

serene mirage
#

i use trig sub for this

molten pivot
#

or just incorporate it into the sub yeah

serene mirage
#

the final page is where im at right now

#

am i doing anything wrong yet

molten pivot
#

looks good so far

serene mirage
#

ill continue and let u know again

#

@molten pivot

#

how about now

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#

@serene mirage Has your question been resolved?

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@serene mirage Has your question been resolved?

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quiet mural
#

i need help with probability

lone heartBOT
vale wigeon
#

image on its way?

gusty gorge
#

let her finish the fortnite game

vale wigeon
#

what fortnite game

quiet mural
#

hold on

#

sorry

vale wigeon
#

in the future, post your question right away, don't say "i need help" then go silent

quiet mural
#

im struggling with something ok but yes i understand

vale wigeon
#

tell us what you are struggling with!!!

#

show us the problem(s)!!

quiet mural
#

it was the ss lmfao

#

but i got it

lone heartBOT
#

@quiet mural Has your question been resolved?

vale wigeon
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#

@quiet mural Has your question been resolved?

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stray merlin
#

im struggling with understanding on how to come to an answer with these problems

chrome salmon
stray merlin
#

i did the first one

chrome salmon
#

use distribution of summation in 2nd

stray merlin
#

how do i do that

#

im lost

chrome salmon
#

summation (a+b) = summation a + summation b for finite sums

stray merlin
#

okay ty

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woeful wind
#

How do you calculate the most additions needed in dijkstras when given the number of vertices?

woeful wind
#

I know the most comparisons is given by 1/2n (n-1)

#

But I'm not sure what it is for additions

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#

@woeful wind Has your question been resolved?

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buoyant cipher
#

Why is c the right answer here

lone heartBOT
carmine reef
#

there are 3 possible shapes

#

top left circle, top right circle, bottom middle circle

#

each one appears in each row and column an odd number of times

undone falcon
#

small dot, 2 small dots. small and big dot, 2 small dots and 1 big dot

carmine reef
#

those are patterns consisting of multiple shapes

undone falcon
#

ah alr

carmine reef
#

no idea why in the world everything is flipped vertically here for the answers

buoyant cipher
#

I see i see, am impressed how fast u understood the problem😭

carmine reef
#

knowing the answer already does help lol

#

actually first i saw that the top left circle was in every single square

#

the top right circle makes a T shape and so i suspect the bottom middle circle also makes a T shape

#

which it does by the answer

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#

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queen hazel
#

If I know one angle is 10 degrees, and the adjacent side is 1410m, what is the length of the opposite side? (The triangle is a right triangle)
How do I find it?
I used the tan= opp/adj rule, but then I got 14100m for the opposite side...
I don't know if my calculations are wrong, but I'm not meant to get this number because I'm literally trying to calculate the height of a building...
If it is right, I probably got the angle wrong...

vale wigeon
#

how did you get 14100 for the opposite side?

quasi vector
#

,w tan10degrees

queen hazel
#

😭

quasi vector
vale wigeon
#

tan(10°) is not 10

queen hazel
#

oh shit

#

what is it then

#

I literally havent learned this 💀

quasi vector
#

tan10° doesn't have a known value

#

you'd need a calculator to find that

queen hazel
#

o

quasi vector
#

maybe your angle is wrong

queen hazel
#

Yeah probably

#

what if it's 30 degrees?

quasi vector
#

do you know what tan30° is?

queen hazel
#

according to the calculator its 0.577350269

quasi vector
#

well

#

,w tan30°

quasi vector
#

tan30° is 1/sqrt(3)

#

you just have to know these values

queen hazel
#

oh

#

Can I round it to 0.6 and try to calculate?

quasi vector
#

why would you need to round

quasi vector
queen hazel
#

So there would be sqrt in my answer?

quasi vector
#

if you wanted you can round the result after multiplying

#

,w 1410/sqrt(3)

quasi vector
#

your answer would be around 814.06

#

whatever unit it is

queen hazel
#

ohhh

#

I get it now

#

I probably have the angle wrong because the actual height of the building is 234.371m lol

quasi vector
#

,w arctan(234.371/1410) in degrees

quasi vector
#

that doesn't seem right.

#

can you send me the entire question?

queen hazel
#

and it's like "Find a building and calculate the height

#

from afar

#

something along those lines

#

so I used elevation and the distance between me and the building

#

to try and calculate it-

#

They said use ratio

#

The distance is 1.41km

#

and my not so accurate method of calculating the elevation without technology said the elevation was 10 degrees

#

so all I know is the adjacent and angle

#

I should recalculate the angle...

#

Thank you for helping me

queen hazel
# ocean seal

But wait does this mean it actually is close to 10 degrees?

quasi vector
#

it does

#

with that height and distance, the angle is 9.4 degrees

queen hazel
#

Just a slight difference in the angle made the answer change so much, wtf

queen hazel
queen hazel
#

Thank you so much

quasi vector
#

,w tan(10degrees) *1410

queen hazel
#

My dumbass thought tan 10 was 10 degrees 🤦

#

Guess not lol

#

But thanks a lot

#

I hope you have a nice life

#

.close

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#
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tepid mango
lone heartBOT
tepid mango
#

how do you figure this out?

lone heartBOT
#

@tepid mango Has your question been resolved?

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robust oak
lone heartBOT
robust oak
#

Find HM

rotund jolt
#

have more information in this question ?

robust oak
#

no

limpid turret
#

AC=7 and AB=6?

robust oak
limpid turret
#

Not enough info

jovial rune
#

is HM parallel to AC?

robust oak
#

idk

robust oak
limpid turret
#

Many things

#

There's no single answer

robust oak
#

it says H is As bisector to Bs projection or smth

jovial rune
#

i think if HM parallel to AC it could solve

robust oak
#

i dont think its parellel though

limpid turret
robust oak
#

yeah its not in english

normal flower
#

Can you translate?

#

We can say M is MP of BC

#

H is the angle bisector of A

#

AB is 6

#

AC is 7

limpid turret
#

Still not enough info. Many values could exist for <BAC. But perhaps HM would remain the same?

robust oak
#

this is put through google translate

#

In the triangle ABC, AB = 6, AC = 7. H was the base of the projection from B on the bisector of A, and M was the midpoint of BC.

#

Find HM

normal flower
#

AH = AC

#

Can we say that?

robust oak
#

why

normal flower
#

HAC = BAH

#

Wait fk

sour sleet
#

Hi

robust oak
#

BAH=HAC?

robust oak
normal flower
#

And BH will be 9.21

robust oak
#

that still doenst make AH=AC

normal flower
robust oak
normal flower
#

BH is 9.2

robust oak
#

how

normal flower
#

This isn't enough

normal flower
normal flower
#

We might need HM value to solve

robust oak
#

In the triangle ABC, AB = 6, AC = 7. H was the base of the projection from B on the bisector of A, and M was the midpoint of BC.
Find HM

#

this was all of the problem

#

maybe ive drawn it incorrectly

limpid turret
#

Ok I looked into it

#

There's enough info

robust oak
#

rlly

normal flower
#

I am seeing angles part

#

Sides aren't enough but angles are

robust oak
#

is there enough angles provided

normal flower
#

Using angles you solve for sides

jovial rune
limpid turret
#

Hint : HM is parallel to AC, but you need to prove it

robust oak
#

what

#

how is hm paralle to ac

limpid turret
lone heartBOT
# jovial rune

As a helper, please do not give out answers that could be copied as a homework solution. Have the student work through the problem themselves and guide them along the way.

normal flower
#

I used angles

#

Good method capitan

jovial rune
#

thanks

robust oak
#

umm

#

HM would be parallel to TC if uh

#

wait

normal flower
#

Where's TC?

robust oak
normal flower
#

Converse Midpoint theorem interesting

#

What's TC actually?

jovial rune
#

ABD is an isosceles triangle and the bisector of it is perpendicular so it has to be median too, so the angle of ABD = angle of ADB, so AB=AD and DC = 1 use the midsole theorem and solve it

normal flower
#

What does T represent?

robust oak
#

T is just BH stretched out

#

For triangle BTC

#

H is the midpoint of BT?

#

@limpid turret

#

but i need to prove it right

jovial rune
robust oak
#

ah

jovial rune
#

because AH is bisector of BAT and its perpendicular so it has to be median, and ABT has to be isosceles triangle too

robust oak
#

ahhhh

jovial rune
#

my english is not that good im using google translate sometimes, sorry about it 🙂

robust oak
#

thank you thank you

#

thank you all

#

finaly

jovial rune
#

your welcome

robust oak
#

ill close it now

#

.close

lone heartBOT
#
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hidden musk
#

Trying my hand at 3c.
This domain and range seems rather difficult like its a composite function or something.

hidden musk
#

Maybe?

#

Or...

#

I got this handout to help determine domain and range...

alpine sable
#

it's been a while, but doesn't the range of f(x) become the domain of gof(x) ?

flat vale
#

we know that x^2 - 5 must first be > 0

#

solve for the root

#

and that will be ur domain

flat vale
#

and then the range is trivial from the domain

flat vale
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#

@hidden musk Has your question been resolved?

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#
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sudden compass
#

So I was studying for my test when I came across this one on the sheet. We are given some formulas for but i'm stilk not really sure as for where to plug the numbers into and why

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#

@sudden compass Has your question been resolved?

tepid mango
#

.reopen

tepid mango
#

one sec

#

so for the first question

#

you would do

#

A = 5000(1+6/4)^7x4

#

i thiiink

#

and then for the second one you would do 9000 = 5000(1+6/n)^nt and jus work backwards

#

@sudden compass

sudden compass
#

Ty

lone heartBOT
#

@sudden compass Has your question been resolved?

lone heartBOT
#
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tidal ingot
#

If S is a gamma random variable with rate lambda , then lambda S is a gamma random variable with rate 1

tidal ingot
#

why is that?

#

been at this for quite a while cant understand it

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#

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broken falcon
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kk

lone heartBOT
broken falcon
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trying to resolve this limit but idk how to resolve from that point

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i was thinking to cancel the n with the -n

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.close

lone heartBOT
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#
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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>.
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karmic osprey
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does anyone know if theres something wrong with my graph for (a) i.

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i got 3 because at x=-1

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both sides is approaching 3

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i got DNE because x=1 has 2 values for (a) ii.

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i got 1 because x=2 has a point at 1 for (a) iii.

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for (b) i got dne because in the chart where the f(x) is it's approaching positive and negative

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instead of being the same sign

chrome salmon
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are these both different questions?

karmic osprey
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and i got 0/8 because of the work shown

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a b and c are 3 different questions yea

chrome salmon
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no i mean the photos

karmic osprey
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oh

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yea

chrome salmon
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can you send clear ones

karmic osprey
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yea

chrome salmon
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the one where you got limits from graph is right

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not here

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delete it

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open your own channel

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this channel is already occupied

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I can't see properly but is the other limit $\lim_{x\to-2} \frac{x^2-4}{x-2}$

ocean sealBOT
karmic osprey
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yea

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x-> 2

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tho

chrome salmon
karmic osprey
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yea

chrome salmon
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the limit is 4 tho

karmic osprey
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oh

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is (a) and (b) right though?

chrome salmon
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x^2-4 = (x-2)(x+2)

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a is right

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what does b asks? it's not visible

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yes DNE is right

karmic osprey
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okay

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how would i solve c

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because the reason why i did what i did

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is because i assumed i should multiply by the conjugate

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since that was what was done to a similar problem

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but im not sure what went wrong

chrome salmon
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you may have done mistake there too

karmic osprey
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thanks

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i think i can figure the last one out

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i was just trying to figure out if i got any wrong

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.close

lone heartBOT
#
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barren wren
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Hello !
My question is:
when has this system no solutions(depending on alpha) ?

barren wren
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I tried to use matrix but I don't remember the theorem

limpid spade
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did u try row reducing

barren wren
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I mean, the fast way

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sorry for not beeing clear

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and they gives us few possible answers

lone heartBOT
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@barren wren Has your question been resolved?

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lone heartBOT
#
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steep moon
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.open

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.reopen

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ok

lone heartBOT
steep moon
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uh

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how do I find odd numbers from even numbers

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so ok

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i was asked how many 3 digit numbers can be formed from 0,2,3,5,and6 my answer is 243

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so how do I find how many here are odd numbers and how many here are even numbers?

lone heartBOT
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@steep moon Has your question been resolved?

peak bough
steep moon
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I thought that one was one of those probability stuff I'm dumb

peak bough
steep moon
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well

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it's like

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5p3

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I'm using the calculator so I just add up the 0,2,3,5,6 and then P 3

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that's how they taught us this

peak bough
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You have done permutations without repetitions here, and have assumed that a number like 222 can't be chosen

peak bough
steep moon
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yes

peak bough
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This is on the right track - using permutations with repetition - but you've done a mix-up on the way

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And forgot to account for something

steep moon
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what did I forget?

peak bough
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Some times these digit-arranging questions can be taken much easier one digit at a time, instead of wondering which "formula" to use

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First think about how many ways the first digit can be chosen

steep moon
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6

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nono

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5

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i miscounted

peak bough
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No

steep moon
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huh

peak bough
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This is the tricky part

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0 can't be chosen as the first digit

steep moon
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oh

peak bough
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Because then it will not be a 3-digit number

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(At least by some definitions)

steep moon
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nah for this one I think its ok to count it

peak bough
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Maybe you do define something like 023 as a 3-digit number in your course?

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When we did something similar in one of my courses, you had to account for 0 in this way

steep moon
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man I shoulda asked her if we would count the ones that start with 0

steep moon
peak bough
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You can do both, and write it down

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They're not that different in nature

steep moon
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oki

peak bough
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We can start with treating 0 as a no-no for the first digit

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So for the first digit, there are 4 ways to choose this

steep moon
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yes

peak bough
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Then for every digit here, how manys way are there to choose the second digit?

steep moon
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5

peak bough
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Yes

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And then for the third digit?

steep moon
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5

peak bough
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Exactly

ocean sealBOT
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Mikkel

steep moon
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100

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multiplied with each other

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so what we doing with

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3

peak bough
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So there are 100 ways to make a 3-digit number

steep moon
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oh

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so we just multiply all the possible ways

peak bough
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Yes

steep moon
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I see

peak bough
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If we didn't care about the 0-thing, the 4 would have been a 5

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And there would have been 125 ways instead of 100

steep moon
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then howd I get 60

peak bough
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You did permutations without repetitions. So you calculated it like if 5 was chosen for the first digit, then it couldn't be chosen for the second or third

steep moon
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I see

peak bough
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Now you need to find the numbers that are even, and the ones who are odd

steep moon
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and how do I do that

peak bough
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Usually even numbers are defined as numbers than can be written on the form 2k where k is a whole number

steep moon
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hm

peak bough
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Odd numbers are usually either defined as simply whole numbers that are not even or a second definition that is often used is a number that can be written on the form 2k + 1 where k is a whole number (some prefer 2k - 1, which is equivalent)

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The first definition for an odd number presented here would be the most useful to use

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Since we just need to find the amount of even numbers and take that away from the total amount of numbers

steep moon
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and how do we do that?

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isn't this a sequence type of equation?

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I think there was some type of arithmetic formula that could maybe help

peak bough
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A neat trick to see if a large number is even is to see if the last digit is even

steep moon
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ohh ok

peak bough
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So something like 19474752 can easily be seen to be even, since the last digit, 2, is even

steep moon
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yes

peak bough
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If you want an explation for why this is, it follows from the fact that a number like 19474752 can be written as 1947475 ∙ 10 + 2 ∙ 1 which can be factored to be on the form of an even number

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(And this logic follows for all numbers with 2 digits or more)

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Okay, back to it

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We know that the even 3-digit numbers have to end on an even digit

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Which are our options for this?

steep moon
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uh

peak bough
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We just want the possible digits our 3-digit number can end on, for it to be even

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From our set of numbers {0, 2, 3, 5, 6}

steep moon
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yeah

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like we gotta find how many 3 digit numbers are even?

peak bough
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Right now we want to find which digits our number can end on

steep moon
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let's say from 100-125? and 100 102 , 104, etc.. that stuff?

peak bough
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Just the third digit of our 3-digit numbers

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Can it end on 0?

steep moon
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oh just

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uh yea

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yes

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I think

peak bough
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Yes

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Because 0 is even

steep moon
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yes

peak bough
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(Can be written as 2 ∙ 0)

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What other numbers as the last digit, would make the 3-digit number even?

steep moon
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2,4,6,8,0

peak bough
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4 and 8 are not part of the digits we can choose

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But otherwise, yes

steep moon
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oh

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oh ok

peak bough
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So we know that the last digit has to be either 0, 2 or 6 for the 3-digit numbers to be even

steep moon
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yes

peak bough
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Now we can do a similar procedure as earlier, but with out new knowledge of the third digit

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How many digits can be chosen as the first?

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(If we don't count 0)

steep moon
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9

peak bough
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No

steep moon
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huh

peak bough
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We have the numbers 0, 2, 3, 5 and 6 to choose from

steep moon
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oh just those?

peak bough
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Yes

steep moon
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oh 4

peak bough
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Yeah