# a riddle i places b4 u

$do$ $u$ $know$ $y$ $i$ $exists?$
$bcos$ $i$ $is$ $that$ $that$ $does$ $not$ $exist$
$in$ $plane$ $terms$ $i$ $wanders:$ $y$ $is$ $i$

$sum1$ $and$ $i$ $in$ $a$ $relationship:$ $its$ $complicated$
$at$ $times$ $i$ $is$ $in$ $heaven$ $with$ $an$ $angle$
$\&$ $other$ $times$ $on$ $the$ $ground$ $-$ $bless$ $i,$ $4$ $i$ $has$ $sin$

• @manshu: What typos? – KeyboardWielder Apr 30 '16 at 19:49
• "bcos" is an abbreviation, not a typo. What's wrong with "angle"? - my spell checker seems to be satisfied with it... – KeyboardWielder Apr 30 '16 at 19:55
• angle is between two lines. While Angel is in heavens. – manshu Apr 30 '16 at 19:58
• When the gates of heaven are opening, isn't there an angle between them? – KeyboardWielder Apr 30 '16 at 20:02
• @JonathanAllan: Seems that adding the right tag to many of my puzzles would end up being a spoiler. ;) – KeyboardWielder Apr 30 '16 at 20:19

I'll take a go at it and say it's

my reasoning:

do u know y i exists? bcos i is that that does not exist

i is something that does not exist

in plane terms i wanders : y is i

This seems like something related to plotting on a coordinate plane: In the complex plane, the y-axis is the imaginary axis representing i -- the imaginary unit.

sum1 and i in a relationship: it's complicated

Now it definitely is a mathematical quantity. and when we add 1 + i we get something "complex": a complex number! so we can confirm that i is the imaginary unit.

at times i is in heaven with an angle

i can be in the exponent of e with an angle, say $\theta$ to get $e^{i\theta}$

&& other times on the ground −− bless i, 4 i has sin

i appears on the ground when we use Euler's formula to rewrite $e^{i\theta}$ as $cos\theta + isin\theta$

• Correct! The topic was the symbol/unit in general (which exists for the purpose of denoting things that don't exist), and not specifically the formula. – KeyboardWielder Apr 30 '16 at 20:27