AP EAMCET2006MathematicsComplex Number
The equation of the locus of z such that | z-i z+i |=2 , where z=x+i y is a complex number, is
Options
- A3 x^2+3 y^2+10 y-3=0
- B3 x^2+3 y^2+10 y+3=0
- C3 x^2-3 y^2-10 y-3=0
- Dx^2+y^2-5 y+3=0
Correct answer
B. 3 x^2+3 y^2+10 y+3=0
Step-by-step solution
| z-i z+i |=2 z=x+i y | x+i y-i x+i y+i |=2 | x+(y-1) i x+(y+1) i |=2 |x+i(y-1)|=2|x+(y+1) i| x^2+(y-1)^2=4 (x^2+(y+1)^2 ) x^2+y^2-2 y+1=4 y^2+8 y+4+4 x^2 3 x^2+3 y^2+10 y+3=0