Complex Numbers And Quadratic Equations question 269
Question: If $ z_1,z_2z_3,z_4 $ are the roots of the equation $ z^{4}=1 $ , then the value of $ \sum\limits_{i=1}^{4}{z_i^{3}} $ is [Kurukshetra CEE 1996]
Options:
A) 0
B) 1
C) $ i $
D) $ 1+i $
Show Answer
Answer:
Correct Answer: A
Solution:
$ z_1=1,z_2=i,z_3=-1,z_4=-i $ \ $ 1^{3}+{{(i)}^{3}}+{{(-1)}^{3}}+{{(-i)}^{3}}=0 $ .
BETA
