+0  
 
+1
139
2
avatar+532 

im thinking for this one it might be 6i sqrt 3

but im not sure i could be wrong

 

 

my guess is -i for this question

 Sep 8, 2018
 #1
avatar+67 
+1

I dont know the first one but the second one is just -i

 Sep 8, 2018
 #2
avatar+4490 
+2

-i is correct though it would be better if you understood why.

 

\(\forall n \in \mathbb{Z} \\ i^{4n} = 1 \\ i^{4n+1}=i \\ i^{4n+2}=-1 \\ i^{4n+3}=-i\)

 

for the first problem we have

 

\(2\sqrt{-27} = 2\sqrt{27}\sqrt{-1} = 6\sqrt3 i = 6i \sqrt{3}\)

 

the 3rd choice

 Sep 8, 2018

39 Online Users

avatar
avatar
avatar
avatar