#help-38

1 messages · Page 53 of 1

tough iron
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Which part is confusing you

bronze eagle
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Everything

tough iron
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Gotta be more specific

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Theres not much to do here

bronze eagle
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The whole question

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I mean

tough iron
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You have 8x-3y and they told you how much X is and how much Y is

bronze eagle
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Yea after that what do I do

tough iron
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After what

bronze eagle
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You said they told me the y and the x okay and

tough iron
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Well if i told you you have 8 boxes and i told you in each box there's 6 oranges

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How many oranges you got

bronze eagle
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8*6???

tough iron
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Yea

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And then i came along and brought 3 bags with me

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And i filled them with 4 oranges each

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How many did i take from you

bronze eagle
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1

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4-3

tough iron
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Are you sure

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I have 3 bags and each has 4 oranges

bronze eagle
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3*4

tough iron
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And then how many oranges do you have now

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After you counted your own and i took some for myself

bronze eagle
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16

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Hold on I'm confused I need help with the question

tough iron
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Okay well i cant teach you the multiplication table

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This IS the question

bronze eagle
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I want to show my work then

tough iron
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Im trying to visualize to you how math works instead of just plopping you the answer

bronze eagle
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No I just need show work not answers

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Okay let's start

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You said what

tough iron
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Lets go left to right

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8x

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That's 8 times X

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Some unknown thing

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You have 8 boxes of oranges but you don't know how many are inside

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And then I come along and tell you X=6

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So now you know there's 8 boxes with 6 oranges each

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How many do you have now

bronze eagle
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How many oranges?

tough iron
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Yea

bronze eagle
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6

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No no

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Wait

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8"6

tough iron
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Which is how much

bronze eagle
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Uhmmm 48?

tough iron
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48

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So you have 48 oranges

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Great

bronze eagle
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Yea

tough iron
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Lets move on

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Then we have -3y

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You are subtracting 3 times some unknown Y

bronze eagle
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Yes

tough iron
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I came with my own boxes and i took some oranges and filled 3 boxes and left

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And then i told you

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Hey my boxes fit 4 oranges

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Which means Y=4

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So how many did i take

bronze eagle
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So in each box 4 or 1

tough iron
bronze eagle
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4

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So

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3*4

tough iron
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Which is

bronze eagle
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12

tough iron
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So if you had 48 oranges and i took 12

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Now you got?

bronze eagle
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36

tough iron
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Thats the solution

bronze eagle
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Ohhh

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But how do I write it

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In the box

tough iron
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What do you think

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After doing this chatting exercise here

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What did you do

bronze eagle
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I know but do I say oranges and stuff

tough iron
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Of course not

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What did you do with the numbers

bronze eagle
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Subtract and multiply

tough iron
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What did you do with these two numbers

bronze eagle
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Wait so 8x6 and 4*4

tough iron
bronze eagle
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Multiply?

tough iron
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3y

bronze eagle
tough iron
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You put the values of X and Y in the equation

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Instead of 8*x you wrote 8*6

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Because x=6

bronze eagle
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Yea

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So I write

tough iron
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And instead of 3*y you wrote 3*4

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Because y=4

bronze eagle
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86 and 34

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So

tough iron
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You put the values of x and y in the equation

tough iron
bronze eagle
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Look let me show you rq

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Like this

tough iron
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Sure i guess

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I'm not your teacher idk how they grade you

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Im just showing you the principle of solving

bronze eagle
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Oh but you think I will get it wrong

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?

tough iron
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I dont know, write * instead of .

bronze eagle
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what?

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Last one blease okay

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Number 3

tough iron
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You should be able to do this one on your own now

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Its just reading comprehension

bronze eagle
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What

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Here in a better picture

tough iron
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Whats 6x

bronze eagle
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Wdym

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It says 6x-2

tough iron
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What does 6x mean

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If you wrote 6x on a board

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How would you explain to a little child

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What that means

bronze eagle
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6 and some random letter but we just put x

tough iron
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What does "and" mean in your sentence

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6 and a number

bronze eagle
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X

tough iron
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Is 6x like saying 6 + X

bronze eagle
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Yea

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Like look

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6 + x =45

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Like this

tough iron
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Ok but we wrote 6x

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Not 6+x

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What does 6x mean

bronze eagle
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I'm just showing

bronze eagle
tough iron
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Just like in the last question

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Question 2 has 6x-3y

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What does 6x represent

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Spoiler because my hair is falling out

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It means 6 TIMES X

bronze eagle
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Bro that's what I was. Saying hey

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Bru

bronze eagle
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Alright so yea

tough iron
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So 6x is the product of 6 and x

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Do you agree

bronze eagle
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Yes

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So is a b c d?

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I mean is it

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A or D

tough iron
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Im not gonna solve your question

bronze eagle
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But you didn't explain bro

tough iron
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What is the difference between A and D

bronze eagle
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How am I supposed to know

bronze eagle
tough iron
tough iron
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They dont mean the same thing

bronze eagle
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Yes

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Soo?

tough iron
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Sooo im asking you

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How do they differ

bronze eagle
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They are different because the number minus the two

tough iron
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How would you write A in numbers

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Product of 6 and a number less than two

bronze eagle
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Yes

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6 and x

tough iron
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How would you write it

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In numbers

bronze eagle
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Is least the 2

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6x -2

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Ooooohhhhh

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Oh shi

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I see now

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Damn I'm good at math

tough iron
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What do you see

bronze eagle
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The number

tough iron
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Which answer would you choose now

bronze eagle
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A

tough iron
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Nope

bronze eagle
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c'mon man

tough iron
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Do you know what "less than" means

bronze eagle
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Negative

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Right

tough iron
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If i tell you 2 is less than 3

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Does that mean 2-3

bronze eagle
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No

tough iron
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Of course it doesnt

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So less than doesnt mean '-'

bronze eagle
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Yea who would say that

bronze eagle
tough iron
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Have you ever seen this sign

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<

bronze eagle
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Greater smaller

tough iron
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Or greather than less than

bronze eagle
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Ye ai learned dem 5 or 6i don't rember long time ago

bronze eagle
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Wait so A is saying that the 6 is less then 2

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That don't make sense

tough iron
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It means 6x where x is less than two

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Or

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6x<2

bronze eagle
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yea it don't make sense

tough iron
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Depending on how you read it

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It doesn't make sense

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That's the point

bronze eagle
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Yea yea

tough iron
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Its not the right answer

bronze eagle
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So we cross 🤞 A

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I think it's D

tough iron
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We cross A

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Well lets check

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What does D say

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A product of 6 and a number minus 2

bronze eagle
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The product of six and a number minus two

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Yea

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But we don't say minus

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It's a negative

tough iron
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How will you write The product of 6 and a number

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In numbers

bronze eagle
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Wdym

tough iron
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Just like i asked you 2 mins ago

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Write " The product of 6 and a number "

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But not in words

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Write it how you would write it in numbers

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You did it 3 mins ago

bronze eagle
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6x -2

tough iron
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When i asked you the same question

tough iron
bronze eagle
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Yes

tough iron
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Not what i asked you

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But whatever

bronze eagle
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D

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Is

tough iron
#

Yes D is the answer, please pay more attention in class

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For your own good

bronze eagle
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6 and a number - 2

tough iron
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Yes

bronze eagle
bronze eagle
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So what

tough iron
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You gotta pay attention

bronze eagle
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Yea my bad

tough iron
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Instead of betting on the phone

bronze eagle
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Yea

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Anyways

bronze eagle
tough iron
#

Yes

bronze eagle
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Yes

tough iron
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I hope youll listen to me because youll have a shit ton of problems in older years if you dont know basic arithmetic

bronze eagle
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Wdym

tough iron
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If you are struggling so much with these basic ass questions and you aren't listening in class

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You'll be one dumbass kid later

bronze eagle
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I'm in 10th so 2 more years and I go to collage play ball and I might make you don't know I don't knowb

bronze eagle
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Ight ight

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So I said thai

bronze eagle
tough iron
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Saying that for your own good I don't care what you do

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Man

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I told you 4 times

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Yes

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6x-2 is that

bronze eagle
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Alright man don't be mean

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We cross D

tough iron
#

Are you also betting while reading this channel

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We dont cross D

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Did you read the question

bronze eagle
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It don't make any sense

tough iron
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They're asking you what 6x-2 is

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You figured D means 6x-2

bronze eagle
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Yes

tough iron
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Why do you cross it

bronze eagle
bronze eagle
tough iron
#

Sorry man i give up my batterys drained

bronze eagle
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Nah c'mon man

tough iron
#

Circle D and good luck

bronze eagle
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I'm sorry man

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So it's D

tough iron
#

Yea

bronze eagle
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Look man do you want me to give you money or boost your servers

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I know you had hard times

tough iron
#

Im good

bronze eagle
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😂

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What do you think

tough iron
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Wish you the best at ball remember to pay attention in class

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See ya

bronze eagle
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Alright

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Peace

tough iron
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You can do it

bronze eagle
#

W

tough iron
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If you want to!!

bronze eagle
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Hope so

bronze eagle
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At the same time

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Can't focus on 2

trim joltBOT
#

@bronze eagle Has your question been resolved?

bronze eagle
#

Yea

trim joltBOT
#
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grave scarab
#

Please help find the equation of a circle passing through points (1, -2) & (4, -3) whose center lies on the line 3x+4y=7.

trim lichen
#

!status

trim joltBOT
#
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 was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
grave scarab
trim lichen
#

you might want to try to find the center.

grave scarab
#

yes. How to.

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I'd think u need to find a point on the given line having distance equal from both points.

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But i don't know how to do that.

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Another method I can think of would be to find the equation of the line created by the points of family of circles passing through those 2 points and find the intersection. But i dunno how to find that eq either...

round mango
grave scarab
round mango
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what is stopping you from using it

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oh my bad

grave scarab
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The fact the it's not certain that the center and the 2 points are coleniar.

round mango
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didnt read the question completely

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i thought those were diametric end points

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yeah anyway

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are you aware of the distance formula

grave scarab
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Yes.

round mango
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Great, if you want to find to find a point h,k such that it is equidistant from the two points, equating the distance will give you one relation between h and k, and then using the condition that h,k satisfied 3h+4k+7 will give you another equation. You will have 2 equations and 2 variables and you can solve for them

#

this obviously is a long and tiring thing imo

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but as you mentioned it, family of circles is a better way to solve this

grave scarab
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What do u think bout let center be (h, k), and them equate the distance from 2 points. Getting an equation of a line. Then get the intersection and that be the center?

round mango
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that is exactly what i said

grave scarab
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oh. Sry, couldn't completely understand :p

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I'll try and report back.

round mango
#

but anyway as i said that way i dont like since it is a little calculative

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Recall that the family of circles passing through the point of intersection of circle S = 0 and line L = 0 is given by S+λL = 0
Now if you think about it youre already given the line L and a circle S

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try to formulate something here

grave scarab
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But we need to find the eq of the circle. And lamda is also unknown.

round mango
#

which will help you eliminate lambda

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you can easily find out the 'L' in the family's eq right?

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and let S just be the circle which has diametric end points as (1,-2) and (4,-3)

grave scarab
#

I think the equation from eating (h, k) will give that line?
I forgot the family of circle part a lil.
L is the line of all the centers or the common cord

round mango
#

L is the common chord yes

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in this case the common chord is the line passing through 1,-2 and 4,-3

grave scarab
#

okey.

trim joltBOT
#

@grave scarab Has your question been resolved?

grave scarab
lost wharf
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*s

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keept x=t and get y with help of line

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then use distance formula

grave scarab
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Didn't get it...

lost wharf
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what's the answer?

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keep centre as (t, 7-3t/4)

grave scarab
lost wharf
#

ok wait

lost wharf
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got it

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@grave scarab

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did u get?

grave scarab
#

Nope...

lost wharf
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ok

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I got it

grave scarab
#

Pls tell

lost wharf
#

ok see

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keep the centre as (h, k) or anything

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then circle cuts the point

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put it in equation (x-h)^2+(y-k) ^2= r^2

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put values of (x, y) given

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then you will get two equations

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subtract them

grave scarab
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But r

lost wharf
#

wait

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we will then use the line equation and put h, k

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then solve the equation from the upper part

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then get h, k

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then we can get radius too

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then the equation

grave scarab
lost wharf
#

ok so since centre lies on line

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h, k will satisfy the line

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therefore we put h, k in line

grave scarab
#

Oh

lost wharf
#

I've solved

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do u want to see

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or u understood

grave scarab
#

Please send. I'mma go solve. Then even if channel closes i can see.

lost wharf
lost wharf
trim joltBOT
#

@grave scarab Has your question been resolved?

trim joltBOT
#

@grave scarab Has your question been resolved?

grave scarab
#

.close

trim joltBOT
#
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trim joltBOT
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Show your work, and if possible, explain where you are stuck.
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wraith hinge
#

Need to differentiate

trim joltBOT
stark bison
#

!status

trim joltBOT
#
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 was told that it's wrong.
4. I got an answer and would like my work checked.
5. I have a question about someone else's work/solution.
6. I have completed the problem and don't need help anymore. Thank you.
7. None of the above
wraith hinge
#

I know that it is supposed to be solved with chain rule

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but i dont really know how to solve it

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@stark bison I don't know where to begin basically

stark bison
#

Can you come up with functions f and g such that f(g(c)) = (6 - 2sqrt(c))^2?

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(Think about what happens to the variable c before the action of squaring)

wraith hinge
#

before suqaring the power 1/2 will be multiplied i guess and 1 would be subtracted from 1/2

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do i have to differentiate inside the bracket first

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i have no idea

stark bison
#

So that f(g(c)) = the given function

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And differentiate using chain rule

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What are f'(c) and g'(c) equal to?

trim joltBOT
#

@wraith hinge Has your question been resolved?

wraith hinge
#

g'(c) for the one inside bracket ig

stark bison
wraith hinge
#

okay

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still like bit clueless

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like

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it will be 2c

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right

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and for 6-2^1/2 we have to differentiate

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as g'(c)

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??

stark bison
wraith hinge
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YES i mean 6-2c^1/2

stark bison
#

Right, what's the derivative of that?

wraith hinge
#

-1/c^1/2

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can u tell like the answer i might have got it

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f′(g(c))⋅g′(c) have to apply this then right

stark bison
#

Yes

trim joltBOT
#

@wraith hinge Has your question been resolved?

trim joltBOT
#
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Ask your math question in a clear, concise manner.
Show your work, and if possible, explain where you are stuck.
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fringe abyss
trim joltBOT
fringe abyss
#

i know to expand giving me a^2 + 24a + 144

#

not sure what to do from there

timid bay
#

you got that for (a+sqrt12)^2?

fringe abyss
#

yes

leaden wyvern
fringe abyss
#

oh

severe stump
#

He's also wrong.

timid bay
#

Its not right either

fringe abyss
#

what

leaden wyvern
#

my b

severe stump
#

Write out each term in the distribution

leaden wyvern
#

realized the screwup

fringe abyss
severe stump
#

(a + sqrt12)(a + sqrt12)

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Should have 4 terms, two of which you combine since they are like.

fringe abyss
#

oh ok lemme work dat out

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a^2 + a sqrt12 + a sqrt12 + 12?

severe stump
#

Yeah, and then you can combine the middle two.

fringe abyss
#

a^2 + 2a sqrt12 +12?

severe stump
#

Yup!

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Now they want you to generalize this into the integer parts and the root parts.

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a^2 is an integer and 12 in an integer.

fringe abyss
#

ok

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so that would be k?

severe stump
#

Right.

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And then they have this n sqrt(3) term

fringe abyss
#

so i have to make 2a sqrt12 into n sqrt 3

severe stump
#

Right. What happens when you factor 12?

fringe abyss
#

sqrt12 is 2sqrt3?

severe stump
#

Right.

fringe abyss
#

so n is 4

severe stump
#

So you would get 4a sqrt(3)

fringe abyss
#

cos 2x2

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oh

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right ye

severe stump
#

But yeah you got the gist.

#

So what are your expressions?

fringe abyss
#

so n is 4a and k is a^2 + 12?

heady trail
#

For compact two-dimensional surfaces without boundaries, if each loop can be continuously compressed to a point, then the surface is topologically homeomorphic to a 2-sphere (usually just called a sphere). The Poincaré Conjecture, proven by Grigori Perelmán, states that the same is true for three-dimensional spaces.

Someone to solve it

severe stump
#

Brother this channel is occupado already.

#

But yeah, n is 4a and k is a^2 + 12

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It's strange that they asked for expressions instead of equations, they must really hate equal signs.

fringe abyss
#

i guess so

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thank u very much tho

severe stump
#

No prob

fringe abyss
#

appreciate it

#

.close

trim joltBOT
#
Channel closed

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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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sleek roost
#

Hello, I am confused about matrix commutation in one particular task - Determine all the matrix that commute with the following matrix:

sleek roost
sleek canopy
#

wow

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it self surely

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maybe if you write the coefficient's equation associated with $AB=BA$ where $A$ is your matrix, you'll get some useful conditions

solid kilnBOT
sleek roost
sleek canopy
#

what have you gotten ?

sleek roost
#

then i got system of equations with 4 unknowns but it doesnt fit with solution which is:

#

wait a moment

low gazelle
sleek roost
#

which is then:

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and for final solution i got (a,b,c,d)= (-3b, b, -5/3 b, 0)

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honestly i dont know where i messed up

winged hinge
#

might need to show ur full work :p

low gazelle
#

You should end up with 2 free variables, so your matrix will be in terms of a and b

sleek roost
#

beacuse i checked now and everything i did in further process was alright

#

how would u do this from here

sleek roost
low gazelle
#

since it is a linear system

sleek roost
sleek roost
#

i went by usual method by eliminating so myb thats the reason i got something else

#

it literally came same shit as i got from eliminating method

#

amazing

low gazelle
sleek roost
low gazelle
# sleek roost

Ok well the first issue I see is that you have only 3 rows when you should have had 4

#

You had 4 equations

sleek roost
#

i removed one row because its repeated

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like two same rows

low gazelle
#

I see

#

Did you use this as your starting matrix?
[0, 5, 3, 0 | 0
-3, -9, 0, 3 | 0
-5, 0, 9, 5 | 0
0, -5, -3 0 | 0]

sleek roost
#

im starting to believe that solution is actually wrong lmao

low gazelle
#

well an equivalent thing

low gazelle
# sleek roost yeah

Probably made some mistake during the process. Do you have the work you did to get to this?

#

To get what u got*

sleek roost
#

i did it on some paper but trust me my handwriting is awful

#

anyways i checked on every possible math solver and it keeps giving me same answer that i got by myself

low gazelle
#

I will give you the matrix im getting so you can atleast see what to do from there

sleek roost
low gazelle
#

[-3, -9, 0, 3 | 0,
0, 5, 3, 0, | 0]

#

Last 2 rows were all zeros implying that there are 2 free variables

sleek roost
#

interesting

low gazelle
#

You know what to do from here?

sleek roost
#

yeah

#

we will see what comes

#

anyways

#

thanks for the help

low gazelle
#

np

sleek roost
#

have good rest of the day

#

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astral skiff
#

hi! i'm new to stats stuff and i wanted to double check to make sure im understanding how to solve chi square test

astral skiff
#

(the data is candies so i just made the expected an equal amount for each color, im not sure if thats correct lol)

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astral skiff
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<@&286206848099549185>

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empty brook
#

Hi, so this isn't urgent since this isn't a homework or anything, but I was wondering If, let's say, I have an event that has a 1/7500 chance of happening, and I trigger that event x times, what is going to be the % chance that it happens at least once for any value that I decide to attribute to x? What is mathemathical function/equation that represents this problem, if there is one?

empty brook
#

Because it definitely can't simply be x/7500, because it is not magically guaranteed on the 7500th try

ionic pendant
#

looks like a binomial distribution problem

#

notice that the binomial distribution models the probability something happens a specific number of times out of all attempts. if you just want to find the probability of happening at least once you can take (1 - probability of happening 0 times)

austere cedar
#

"At least once" has a nice formula, you'd use
1 - (1 - 1/7500)^x

empty brook
#

oh ok

#

makes sense

austere cedar
#

You can answer more general questions like "what is the probability of exactly twice" with the binomial distribution, which is worth seeing

empty brook
#

ok cool

#

probabilities are so cool

#

and fun to play around with

austere cedar
#

Agreed haha

empty brook
#

anyways thanks for the answers, both of you, how do I mark my problem as solved?

austere cedar
#

You can do .close to "return the channel"

empty brook
#

ok thanks

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cerulean hearth
#

what's the trick to solve that?

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wraith hinge
#

*dividing and multiplying

cerulean hearth
#

hum

#

i don't see how it is easier to calculate this

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split chasm
#

harmonic trig identities to express the sum as a single trig function

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karmic kernel
#

,rotate

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solid kilnBOT
karmic kernel
#

Solve for u

#

(Using ln)

#

,rotate

solid kilnBOT
karmic kernel
#

I got this far but dont really know what to do next

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keen void
#

$ln(3^x + 3^{x+1}) = 1$

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solid kilnBOT
#

Merineth

keen void
#

I need a hint on where to start

#

Solve x

atomic socket
#

take 3^x out

#

3^x ( 1 + 3)

#

so 3^x*4

keen void
#

How? Since I have 3^x+1

atomic socket
#

4 * (3^x)

#

3^(x+1) = (3^x )* 3

#

so we will get sometihng like this:

4*(3^x) = e

#

3^x = e / 4

#

so x = log_3(e/4)

keen void
#

The answer is 1-ln(4)/ln(3)

#

But hold on, how do I break out 3^x out of 3^x+1

atomic socket
#

3^(x+1) = 3*3^x

#

i already say that xd

keen void
#

So the +1 represents a 3?

atomic socket
#

ye u know why?..

#

if u dont know why we are wasting time here i think

atomic socket
keen void
#

Alright, sorry

#

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lethal fog
#

I am trying to calculate the volume of a cylinder because of an aquarium idea I had.
The units start in imperial units and I need them in metric, because imperial sucks.

(((12^2•Pi)•36)•(2.54^2/1^2))•(1^2/1000^2•9)

I replaced * with •

lethal fog
#

I have no idea how to use volumetric math

nova spire
lethal fog
#

I am using inches.
12^2 is its radius squared

#

36 is its height

#

2.54 was my attempt to convert it to cm

nova spire
#

and both expressed in inches I guess

lethal fog
#

Yes

nova spire
#

ok

#

r = 12in,
h = 36in

lethal fog
#

Aye

#

The rest of the equation was my attempt at converting to liter

nova spire
#

so in a first part, if you want the final volume to be in L = dm^3

#

convert r and h to dm, and you will get your answer

#

(1dm = 10cm)

#

also, 1in = 2.54cm

lethal fog
#

Ah, thank you very much, so (((12in(2.54cm/1in)^2)Pi)(36(2.54/1))?

nova spire
#

That will give you the volume in cm^3, so progress!

lethal fog
#

Ah, then multiply that by 1/10?

nova spire
#

be careful about parentheses tho

nova spire
nova spire
lethal fog
#

I study chemistry, i had to teach myself allcthe math I know, and I never needed cubed, just mL. L

#

Ah

nova spire
#

ok so

#

so this is the volume in cm^3. How to convert cm^3 to L = dm^3?

#

since 1dm = 10cm, 1dm^3 = ...

lethal fog
#

Im having trouble understanding that

#

Is 1dm 10 cubic cm, as in 10cmx10cmx10cm?

nova spire
#

1dm is not "10 cubic cm"

#

But you are correct as in 1dm^3 = 10cmx10cmx10cm

lethal fog
#

Ah, so to get my answer in liter, I would have to convert feom inches, to cm, to dm and then do the equation?

lethal fog
#

(((12in(2.54cm/1in)(1/10))^2)Pi)(36in(2.54cm/1in)(1/10))?

nova spire
#

So r = 12in = 12*2.54 cm = 12*2.54/10 dm

nova spire
lethal fog
#

Wooo, ima need to juice a lemon on my noggin to wrap around that one, Thank you very much, Rafilou

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stoic flare
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stoic flare
#

How do I do this i can't even do cos

ornate kiln
stoic flare
#

The main one

ornate kiln
#

you cant do it

#

with only 2 data given

stoic flare
#

Ok what about this

ornate kiln
#

this is a normal exercise now

#

not just a thumbnail

stoic flare
#

Ok.

#

So

cedar nacelle
#

You have 90 degrees at the bottom which means the adjacent angle must also be 90 degrees which means you can apply the SOH CAH TOA rules

stoic flare
#

If 90 is for that triangle would the adjacent line also be 90 or 52 ?

cedar nacelle
#

It would be 90

#

Remember that a straight line has an angle of 180

#

Since this line is 90 degrees it means it is perpendicular to the horizontal.

#

This also means that the adjacent angle will also be 90

stoic flare
#

But then why is the other triangle 52

cedar nacelle
#

52 represents the height in this case

#

There’s multiple ways to solve it

stoic flare
#

For first I think it's tan 90/x

cedar nacelle
#

For which angle alpha or beta

stoic flare
#

ALPHA

cedar nacelle
#

What are you using tan 90

#

if you split the triangle into two separate triangles then try to solve for angle

#

You could also use Pythagorean theorem to since the missing side then use tan

stoic flare
#

Pythagorean with what

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#

@stoic flare Has your question been resolved?

cedar nacelle
#

its a right tringle to you can use it to find the missing side of the triangle

#

i suggest you focus on one triangle at a time

#

you can split it up like so

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calm quartz
#

My proof:

If a is congruent to b (mod 5), then a - b = 5k
If x is congruent to y (mod 5), then x - y = 5m
If a + x is congruent to b + y, then:
(a + x) - (b + y)
= (a + x) -b - y (by distribution)
= (a - b) + (x - y)
We know that a - b = 5k
And x - y = 5m,

So, (a - b) + (x - y) = 5k + 5m
5k + 5m = 5(k + m) = 5(n) where n = k + m
The product of 5n will always be divisible by 5.

This concludes the proof.

I'm new to proofs (this is probably my 5th one). This is what I came up with, but I'm not sure if I made any mistakes. It feels like I took some stuff for granted.

calm quartz
#

It's also possible I misread what it was asking. Been doing problem sets for like 4 hours, so my brain is mush.

merry bluff
#

No, seems good

calm quartz
#

Awesome. Thanks a bunch 🙂

worthy eagle
#

!done

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pallid vine
#

how do part a)

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pallid vine
sleek canopy
#

just plug in that basis vector and see that they are in the plane

#

now plane has dimension 2 so the basis would have 2 vectors

#

notice that the two vector in B are idipendent

pallid vine
sleek canopy
#

i haven't understood

pallid vine
sleek canopy
#

yes

pallid vine
#

ic ok

pallid vine
#

do i just plug in the vecto for x1 x2 x3 as well

sleek canopy
#

i think is easier than a) ...if you couldn't do b) maybe we have to re study some theories

pallid vine
#

dyk what i mena

#
  • im on 1 hour of sleep
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wraith hinge
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wraith hinge
#

how is the 4m in the numerator

#

would it not be 1

nimble stone
#

what do you mean?

wraith hinge
#

like what did they do to get the 4m in the numerator for the second part

nimble stone
#

$(4m^2)^{-\frac{2}{3}}\cdot 4m=\frac{1}{(4m^2)^{\frac{2}{3}}}\cdot 4m$

#

they just did that

wraith hinge
#

instead of the 4m

nimble stone
#

yeah, and they multiplied this by 4m...

wraith hinge
#

oh i see

#

thanks mate

solid kilnBOT
#

AℤØ

wraith hinge
#

got it ty

#

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pliant frost
#

Bicyclists Brent and Jane started at noon from points 60 km apart and rode toward each other, meeting at 1:30 PM. Brent's speed was 4 km/h greater than Jane's speed. Find their speeds.

silent canyon
#

!status

trim joltBOT
#
What step are you on?
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5. I have a question about someone else's work/solution.
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atomic geyser
#

If $Y\sim\text{Poisson}(1)$, what is $E[(Y+1)^k]$?

solid kilnBOT
#

jsidind810

trim joltBOT
#

Please don't occupy multiple help channels.

mystic veldt
#

!1c

trim joltBOT
#

Please stick to your channel.

atomic geyser
#

Yall so quick to do stuff like this but never help

mystic veldt
#

LMAO true

atomic geyser
#

canu help?

mystic veldt
#

no, i dont mind all these multiple channel occupations, i would have already helped u if i knew how to

#

also i just saw that u have diff question in your another channel

#

so according to rules you can hold multiple channels

atomic geyser
#

<@&286206848099549185>

#

If $Y\sim\text{Poisson}(1)$, what is $E[(Y+1)^k]$?

solid kilnBOT
#

jsidind810

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cursive arrow
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cursive arrow
#

how do i times these two

odd onyx
#

dot product

#

not multiplication

cursive arrow
#

so 4s +1 1 + s-4 + 0*2 + s^2 +1`?

odd onyx
#

err

#

close

#

(4s+1)(1) -4(s) +0(2) +s^2(1)

cursive arrow
#

that is what i tried to write

odd onyx
#

ah alright then you're right catthumbsup

cursive arrow
#

but that doesnt give me the right answer

#

i cant see what ive misscalculated

odd onyx
#

should be v^2 + 3z^2

cursive arrow
#

oh

#

yes that is why

#

so s^2 + 9

#

i got s^2 + 1

#

thank you

odd onyx
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tame notch
#

If zero is in the denominator AND in the numerator, is the solution Zero or is it undefined ?

cerulean hemlock
#

do you mean 0/0? It's undefined

tame notch
#

Yes, I mean that

maiden hare
#

x/0 is undefined, whatever x is

tame notch
#

Ok thx everyone

#

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slate barn
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wooden plover
#

yea?

slate barn
#

show that this is linear subspace of R^n*n

#

how?

wooden plover
#

whose subspace is it?

slate barn
#

yo mamas

rose grotto
#

when did jt become a subspace?

wooden plover
#

yeah aight

#

time for some definition spamming

#

what does it mean to be a subspace?

#

you shouldn't be scared by the matrices, it's always the same thing each time no matter what

slate barn
#

so subspace is some non empty set which includes every linear combination of some vectors r and s

#

if i am right

wooden plover
#

if r and s are in the subspace, then ar+s is in the subspace yea (a is a scalar/number)

#

I just state it in the more usual manner

#

or you could just show addition or multiplication seperately

#

what are you used to when you prove smth is a subspace?

slate barn
#

maybe addition ig

#

do i have to do both?

wooden plover
#

yeah

#

you need all linear combinations

#

if you can't scale it's a bit unfortunate

slate barn
#

hm so to be sure i need to prrove that for some vectors eg r,s from X this exiation holds true?

wooden plover
#

no

#

you want to prove

  1. it's not empty
  2. if r and s are vectors in the set, then r+s is in the set
  3. if r is in the set, then a*r is in the subset for all numbers a
slate barn
#

hm alright im gonna try to do that and update you later

wooden plover
#

aight

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#

@slate barn Has your question been resolved?

slate barn
#

so i watched som video to understand it better but they all had easier examples

#

first point is pretty easy i just multiply everything by zero and i should get 0 shouldnt I? @wooden plover

#

but on the next step i am not sure what to do exactly

#

i dont know if even what i wrote is right

#

in 2 and 3

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#

@slate barn Has your question been resolved?

wooden plover
#

@slate barn re was playing a game

#

seems like you're going a bit backwards for 2, but hey we all do that the first time

#

but yeah the idea is right

#

you want to show X+Y is in the subset

#

ie. A(X+Y) + (X+Y)^T B+... = 0

#

start from the left side

#

simplify all you can

#

and get to 0

#

and same for 3

slate barn
wooden plover
#

well go backwards from what you did

#

expand everything

#

(and don't forget the number 1 rule, you suppose that AX + X^TB + ... = 0, and AY + Y^TB + ... = 0)

#

never forget your hypotheses

#

@slate barn

slate barn
#

ahhh alright that seems straight forward

#

is this it?

wooden plover
#

yeah

slate barn
#

noice

#

annd for multiplication I take out g so i will get g(AX+XB+...)=0 so g0=0 and thats it?

#

when g is some scalar

wooden plover
#

yeah

slate barn
#

nice

#

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wraith hinge
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can someone explain why adding p + u gives you the position vector q?

wraith hinge
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<@&286206848099549185>

thorny escarp
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Hadoo

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Idk if this is understandable but, Adding the vector u to the point p gives the position vector q because it represents the displacement from point p to point q by adding corresponding components of the vectors.

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@wraith hinge

wraith hinge
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I sort of get you, I am going to quickly plot p and u to see what you mean

nova spire
wraith hinge
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Would it not be p - u?

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I get what you mean, visually it is not making sense to me though

nova spire
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Oops sorry

nova spire
wraith hinge
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does this visualisation kind of look right?

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sorry my brain is so friend I am struggling to understand anything currently

trim joltBOT
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@wraith hinge Has your question been resolved?

wraith hinge
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.close

trim joltBOT
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wispy kiln
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for base case we can say F2 = F0 + F1 which is 2 and satsifies the fibonacci sequence
for hypothesis we can use strong induction and say Fn = Fn-1 + Fn-2 is satisfied for all n greater than or equal to 2
For the induction step we can assume the hypothesis but I don't see how to show that F3n+2 is even and F3n+1 and F3n are both odd from it???

wispy kiln
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🙏

onyx heart
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try to write $F_{3(n+1)}$, $F_{3(n+1)+1}$ and $F_{3(n+1)+2}$ in terms of $F_{3n}$, $F_{3n+1}$ and $F_{3n+2}$. then you can use the induction hypothesis

solid kilnBOT
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Robin123

wispy kiln
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Hello I could write F3n + 2 = F3n+1 + F3n but i still dont see how I can use Fn = Fn-1 + Fn-2 to show they are even and odd? I dont see if there is anything substitute? @onyx heart

onyx heart
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so you assumed that the statement is true for n. Now you can for example show that $F_{3(n+1)}$ is odd by using $F_{3(n+1)} = F_{3n+2} + F_{3n+1}$.

solid kilnBOT
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Robin123

wispy kiln
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how??

onyx heart
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you know that $F_{3n+2}$ is even and $F_{3n+1}$ is odd by the induction hypothesis. so what does this imply for the sum

solid kilnBOT
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Robin123

wispy kiln
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how do you know F3n+2 is even and F3n+1 is odd what?

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if its even it has to be divisble by 2 and if its odd it has to equal 2x+1?

onyx heart
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you assume that this is true in the induction hypothesis. the base case is true since F0 = F1 = 1 and F2=2

wispy kiln
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ok but you dont always add even with odd

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for example f3 is odd or 3 and f4 is odd or 5

onyx heart
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i mean all fibonacci numbers of the form $F{3n+2}$ are even and of the form $F{3n+1}$ and $F_{3n}$ are odd.

solid kilnBOT
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Robin123

wispy kiln
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but how did you prove that tho?

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I dont get how you went from F0 = F1 = 1 and F2 = 2 to F3n+2 is even and F3n+1 and F3n is odd

onyx heart
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the base case for the induction to prove the statement is n=0. For n=0, F3n+2 is even and F3n+1 and F3n is odd because F0 = F1 = 1 and F2 = 2. Now you assume that this holds for some n. this is the induction hypothesis. from that you prove that it also holds for n+1

wispy kiln
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so if i plug in 0 for n in that case it is even and odd but isn't it asking me to prove for all n >= 2 not just for n = 0?

onyx heart
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in order to prove that statement by induction you first need to prove the statement for a base case (here n = 0). After that you proceed to prove the statement for all n >= 0

wispy kiln
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ok i see

onyx heart
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the part with n >= 2 is just the definition of the Fibonacci sequence

wispy kiln
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what

onyx heart
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i mean in the first line the fibonacci sequence is defined. after that the statement holds for all n >= 0.

wispy kiln
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ok so because the fibonacci is always in the sequence of even odd odd even odd odd even ...

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by the definition

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then every 3n +2 has to be even

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and 3n + 1 and 3n is odd

onyx heart
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no, the definition of the fibonacci sequence is $F_0 = F_1 = 1$ and $F_n = F_{n-1} + F_{n-2}$ for n >0 2. From this definition you can prove that it is always odd odd even odd odd even ...

wispy kiln
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hmm ok

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i think i get it now

solid kilnBOT
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Robin123

wispy kiln
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thanks

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i will try to prove it

onyx heart
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no problem

wispy kiln
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.close

trim joltBOT
#
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lunar parcel
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How to solve something like this? Should the answer be e^{-\frac{1}{x}}-e^{-\frac{1}{2}}+2?

wispy sparrow
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$e^{-\frac{1}{x}}-e^{-\frac{1}{2}}+2$

solid kilnBOT
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chlamydia

tough iron
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depends if x is >2

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Its an integral from 0 to 2 of tdt and then an integral from 2 to x of 1/t² e^(-1/t) dt

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You split it in two, where the function changes

lunar parcel
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Yes, I came to this answer this way

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but like

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But this is the whole exercise and then it asks why it is continuous and is it differentiable. I want to say it is not continuous, because when you look at this answer in desmos it is not

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the limit at x=0 not the same as value

tough iron
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To check if its continuos you should first find what the possible discontinuities are

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The value t=2 is a good contender

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Because that's where the function splits

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Changes shape so to say

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So to see if its continuous its smart to see if it approaches the same value from the left and from the right

lunar parcel
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But if the exercise asks for continuity of F(x) then I need to check the continuity of the f(t)?

tough iron
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Oh the continuity of F(x)

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Well then just check the expression you get when integrating

tough iron
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If you integrated correctly

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And i think you did

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Seems continuous to me

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Except in one place

lunar parcel
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Okay, then I don't understand continuity 😄 Like okay, this is what desmos shows. Is it continuous at 0?

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no way

tough iron
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Yeah , you do the same approach

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You see if there are any hotspots

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1/x in the power

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x=0 can be a possible discontinuity

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So you check the left and right limit

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To see what happens

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When it approaches 0+, lim e^(-1/x) is e^(-inf) which is 0

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All good

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So the left side must also approach 0 if it was continuous

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However the limit as it goes to 0- is e^inf which is inf

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As seen on the graph

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Which means the function is not continuous, it has a discontinuity on 0, seen on the graph

lunar parcel
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Yeah, so this is an error in the question or should I like say it oh this is not continuous actually. Because it doesnt ask whether or not it is, but why it is continuous

tough iron
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You should say F(x) is not continuous, it has a discontinuity on x=0

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The only way it can be continuous

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Is if you restrict the domain

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It might be that because F(x) is an integral from 0 to x

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It only takes in values in that range

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And you got a discontinuity from 0- which isn't in there

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Im not sure why the textbook says its continuous, thats the only reasoning i can think of

lunar parcel
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Oh so like the function is only from 0? like (0, x]