Complex Numbers And Quadratic Equations question 361
Question: A point z moves on Argand diagram in such a way that |z -3i| $ =2, $ then its locus will be [RPET 1992; MP PET 2002]
Options:
A) $ y- $ axis
B) A straight line
C) A circle
D) None of these
Show Answer
Answer:
Correct Answer: C
Solution:
$ |z-3i|=2, $ let $ z=x+iy $
Þ $ |x+i(y-3)|=2 $ Squaring both sides, we get $ [x^{2}+{{(y-3)}^{2}}]=4 $
Þ $ x^{2}+y^{2}-6y+5=0 $
BETA
