Q.
Let z1,z2 and z3 are the points on the argand plane which lie on the circle with equation ∣z−z0∣=34 (where z0 is the centre of the circle). If z1=0,z2=−4 and z3=4+3z0, then (where arg Z∈(−π,π]) )
4124
203
NTA AbhyasNTA Abhyas 2020Complex Numbers and Quadratic Equations
Report Error
Solution:
Here 3z1+z2+z3=z0⇒z3=4+3z0
Therefore, center coincides with the circumcentre ⇒ Triangle is equilateral ⇒∣z1−z2∣=4
Clearly, z3 either lie in the second or third quadrant
So the centre z0 also lies in the second or third quadrant. ∴z0 can be =−2+32i,−2−32i ⇒arg(z0)=65π,67π