#complex number be getting too complex

110 messages · Page 1 of 1 (latest)

dusk bane
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where did I go wrong and what is the right answer to this?

dawn sinewBOT
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pastel mirage
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the second part is wrong

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and the top part is right

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let me explain why

dusk bane
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yes please

pastel mirage
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here is the mistake

ashen relicBOT
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wolfqz

pastel mirage
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the thing is the you cannot split the root like that when dealing with negatives inside the root

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you have to be very careful

dusk bane
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is that a convention or is there a reason ?

pastel mirage
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as the above result literally breaks math

pastel mirage
dusk bane
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it does lmao

pastel mirage
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but its intuitive

dusk bane
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how is it intuitive?

cold sorrel
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no your step to is wrong

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wait sorry

dusk bane
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feel free to judge critically as it will help me in remembering this mistake

cold sorrel
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wait i texted a similar exp for one more q

pastel mirage
pastel mirage
cold sorrel
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let me get it

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looks like it was closed

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suppose i have a number 4
so now i am asked to find root 4
i will use this idea
rootof 4=root of 22
so i can say root 2 root2 =root 4
so then i say 2=root 4
but now lets try another way
root 4=root -2
-2
root -2
root -2 should be equal to root of 4
so lets do it

pastel mirage
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i already showed this but with 1

cold sorrel
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so i get root2 * root 2 i^2=root 4
it becomes root 4
i^2=root 4
and we get -root 4 =root 4
which makes no sense
as rhs = equal to lhs

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oof sorry

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so we cant split with negative

dusk bane
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aah but root-2.root-2 gave us -4

pastel mirage
cold sorrel
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no it gave - root 4

pastel mirage
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yeah

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you edited that lmao

cold sorrel
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still it is root

pastel mirage
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what

dusk bane
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I see so basically we can't go on splitting numbers into negatives while they are under roots

cold sorrel
dusk bane
cold sorrel
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hm the point came out of no where

pastel mirage
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- root 4

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it adds a point

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  • abc
cold sorrel
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oh

pastel mirage
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the hyphen

cold sorrel
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dman

pastel mirage
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if you dont add a space it doesnt

cold sorrel
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damn

pastel mirage
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lmao

cold sorrel
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asterisk does italics

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btw bot is up and working nice work

dusk bane
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is it like

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9=9

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sq.root both sides

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3=-3

pastel mirage
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what

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bro no

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kind of, i guess

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but square roots, by convention, output the principal value

cold sorrel
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yeah you have |a|

dusk bane
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what do you mean by principal value?

cold sorrel
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mod

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ulus

pastel mirage
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no

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think of it, kind of like the first value

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for square roots it acts like a modulus

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i wont go into much depth but it may be different for other functions (eg lambert w function)

dusk bane
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yes

pastel mirage
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dw about it

dusk bane
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right?

cold sorrel
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modulus

pastel mirage
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yeah

cold sorrel
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and mod is different

pastel mirage
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mod represents modulo

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but you didnt put an input for it so its okay

cold sorrel
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yeah that is for remainders

dusk bane
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what is modulo ?

cold sorrel
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modulus is represented by |a|

pastel mirage
cold sorrel
dusk bane
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I see

cold sorrel
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its to do with remainder in the most simplest sense

pastel mirage
dusk bane
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or -3=-3

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right?

pastel mirage
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NOT

cold sorrel
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no sign

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its always positive

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|-2|=2

dusk bane
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yes

cold sorrel
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|3|=3

dusk bane
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sorry about that

cold sorrel
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no problem

dusk bane
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thank you @cold sorrel and @pastel mirage for answering my doubt

upbeat oarBOT
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@dusk bane has given 1 rep to @pastel mirage @cold sorrel

dusk bane
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I learnt a lot (:

vestal hull
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Wait

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😂

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9=sqrt((-9)(-9)) = 3i x 3i = 9i^2 = -9

pastel mirage
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we already explained how that could not be

dusk bane
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can't split negatives under square roots

vestal hull
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Rightt