I think whoever put ln(i) have some more thought than those who used calculators or memorized to put 0 as answer. Cause
e^(i*pi) = -1
ln( e^(i*pi) ) = ln(-1)

=> ln(-1) = ln(abs(-1)) + i * angle(-1) = ln(1) + i * pi = i * pi

so I think their distinct memory of this formula make them think ln(i). Amazing

That's neat. You could be right.
Or, it could have been a random guess.

I would say in most cases a random guess is more likely because anyone who knew that formula would likely also know the correct answer.

I think a lot of people who weren't familiar with the equation chose ln(i) cause it looks the most apart from the others. That, and I assume most incorrect guessers thought an equation with that many "weird constants" shouldn't have such a simple answer.

I mean, if I didn't know that equation and was too lazy to use google/TI-89 to figure it out, I would have picked ln(i) as well. (Or perhaps the "Huh?" option.)

on a ti 83+ you can do the second button then decimal point button

Still doesn't change the fact that they're wrong :-)

yes but u would find the value of the exponent wouldnt u?

Duh.

My words (or word, in this case) exactly.

Yes.

That was EASY (on a ti84+se)!!!
I just typed it into my calculator and here's the answer.
I don't know what any of those weird letters mean, but they're on my calculator, so I guess it's just that easy.
Hopefully I'll learn what they mean next year.

Yea! You can use a calculator! Well, my titanium will do it TOO! AND I know it by heart!

Uh, weird letters? You mean pi, e, and i?

e^(pi*i) +1 =
the answer seams firmiler, now i remember it is the same as my GPA

as is mine my good friend

??? It shouldn't exist because you end up getting ln -1 = pi*i, which doesn't exist because logarithms aren't defined for negative numbers

You can change your mode to a+bi to get a nonreal answer so then...
ln -1 =3.1415..*i