Question
A(z1), B(z2) and C(z3) be the vertices of an equilateral triangle in the argand plane such that ∣z1∣ = ∣z2∣ = ∣z3∣. Then which of the following is false ?
is purely real
is purely imaginary
- none of these
The correct answer is: none of these
Since ∣ z1 ∣ = ∣ z2 ∣ = ∣ z3 ∣
\OA = OB = OC

\origin is the circumcentre of equilateral triangle ABC.
\
and 
\
is true
Let
\

Now
i.e. if
i.e. if
i.e. ifr2 = r2 which is true.
\
is wholly real i..e. (a) is true.
Similarly (b) is true
Hence (d) is correct
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