Question
Question: If amp. [z<sub>1</sub> (z<sub>3</sub> – z<sub>2</sub>)] = amp. [z<sub>3</sub> (z<sub>2</sub> – z<sub...
If amp. [z1 (z3 – z2)] = amp. [z3 (z2 – z1)], then –
A
z1, z2, z3 are collinear
B
z1, z2, z3 are the vertices of an equilateral D
C
O, z1, z2, z3 are concyclic
D
None of these
Answer
O, z1, z2, z3 are concyclic
Explanation
Solution
Sol. Amp. [z1 (z3 – z2)] = Amp. [z3 (z2 – z1)]
\ amp. [z3(z2−z1)][z1(z3−z2)] = 0
z3(z2−z1)z1(z3−z2) is purely real
z1 , z2 , z3 are concyclic
For four concyclic points (z1−z4)(z2−z3)(z1−z3)(z2−z4) is purely real.