Question

If |z| = 5, then the points representing the complex number – i + $\frac{15}{z}$ lies on the circle

• A. Whose centre is (0, 1) and radius = 3
• B. Whose centre is (0, –1) and radius = 3
• C. Whose centre is (1, 0) and radius = 15
• D. Whose centre is (–1, 0) and radius = 15

Answer 1

Answer: (B)

Whose centre is (0, –1) and radius = 3

Answer 2

Sol. Let w = – i + $\frac{15}{z}$, then i + w = $\frac{15}{z}$

\ | i + w | = $\frac{15}{|z|}$= 3

is a circle with centre at (0, – 1) and radius = 3