Experimental test to train myself before getting into high school
This is the easiest question btw
(Update): turns out I was overthinking because of sleep deprivation haha, it’s solved now
61 messages · Page 1 of 1 (latest)
Experimental test to train myself before getting into high school
This is the easiest question btw
(Update): turns out I was overthinking because of sleep deprivation haha, it’s solved now
the famous imaginary constant defined by $i^2 = -1$
clôud
The encircled problem doesn't seem to mention it anywhere tho.
i am referring to the calculator output
no idea what the relationship is between the calculator and the problem
Aah
Okay, so just looking at your calculator input
Not the problem
but every cubic function has 3 roots, this is a result of a theorem
unnecessary to know why
but these roots aren’t always real
a real number is just our basic number line
What the fu
Got it thanks 
well you can ask the question then, if the square root of 4 is 2
what’s the square root of -4 ?
There isn’t?
it can’t be 2 as 2•2=4≠-2
there is!
it exists in something called the complex plane
these are also called imaginary numbers
it’s described such that
$\sqrt{-1}=i,,i^2=-1$
OK32
these numbers help us work with cases such as this
roots of a negative number
mathematicians for centuries simply ignored them, treated them as fake
BUT
they do exist and are actually incredibly useful in computations
famously very useful in shrodinger’s wave function
but so that is all your calculator is telling you
4i is nothing but
$4i=4\sqrt{-1}=\sqrt{-16}$
OK32

don’t be scared of them
just a simple mathematical trick
to give us a way to work with something that our number system didn’t let us
think of it more as just something that wasn’t planned for
so we had to find a way around it without starting anew
Got it
Goodluck with your learning!
Great job!
Did a redo 15 minutes later
Now it’s correct
Thank you for blessing me with your knowledge @distant obsidian
Wait a damn second
BLYAT
This is solved now
Rookie mistake
good
if you are done with the thread and do not have any other query, you can close it by typing .close or .solved 
.solved