Question

The centre of the circle az$\bar{z}$+ (b–i)z +(b+i) $\bar{z}$–1= 0,(a,b,ĪR) is (5 + i) then:

• A. |a + b| = 5
• B. a = –2, b = 6
• C. a = –2, b = 6
• D. Radius of circle = 5

Answer 1

Answer: (D)

Radius of circle = 5

Answer 2

Sol. –$\frac{b + i}{a}$= 5 + i Ž a = –1

b = –5

radius =$\sqrt{|5 + i|^{2} - 1}$= 5