Let z and ω be two complex numbers such that |z|≤1, |ω|≤1 and |z+iω|=|z−iω¯|=2 , then Z equals
see full answer
Your Exam Success, Personally Taken Care Of
1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.
An Intiative by Sri Chaitanya
a
1 or i
b
i or –i
c
1 or –1
d
i or –1
answer is C.
(Unlock A.I Detailed Solution for FREE)
Best Courses for You
JEE
NEET
Foundation JEE
Foundation NEET
CBSE
Detailed Solution
We have 2=|z+iω|≤|z|+|ω| ∴|z|+|ω|≥2But given that |z|≤1 and |ω|≤1⇒|z|+|ω|≤2From (1) and (2) |z|=|ω|=1Also|z+iω|=|z−iω¯| ⇒|z+iω|2=|z−iω¯|2 (z+iω)(z¯−iω¯)=(z¯+iω)(z−iω¯)⇒zz¯+iωz¯−izω¯+ωω¯=zz¯−izω¯+iωz+ωω¯⇒ωz¯−ω¯z+ω¯z¯−ωz=0⇒(ω+ω¯)(z¯−z)=0z=z¯ or ω=−ω¯⇒Im(z)=0⇒Re(ω)=0Also |z|=1 , |ω|=1⇒z=1 or −1 and ω=i or −i