Home
Class 12
MATHS
If z1ne-z2 and |z1+z2|=|1/z1 + 1/z2| th...

If `z_1ne-z_2` and `|z_1+z_2|=|1/z_1 + 1/z_2|` then :

A

`0 le A le 15/2`

B

`0 lt A lt 15/2`

C

`0 le A le 17/2`

D

`0 le A lt 17/2`

Text Solution

Verified by Experts

The correct Answer is:
D

We observe that `|z-3| le 4` represent the set of all interior and boundary points of the circle having center at `(3,0)` and radius 4.
The equation `|z-1|+|z+1|=3` represents the set of all points lying on the boundary of the ellipse having its two foci at `(-1,0)` and `(1,0)` and major axis of length 3.

Clearly, `A=|z_(1)-z_(2)|=0` when `z_(1)=z_(2)` (=affix of P or Q)
`therefore "min".|z_(1)-z_(2)|=0`
Also, `A=|z_(1)-z_(2)|`is greatest when `z_(1)` = affix of B and `z_(2)`= affix of a.
`therefore` max. `|z_(1)-z_(2)|=A^(')B=A^(')O+OB+3/2+7=17/2`
Hence, `0 le A le 17/2`.
Promotional Banner

Topper's Solved these Questions

  • COMPLEX NUMBERS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Section II - Assertion Reason Type|15 Videos
  • COMPLEX NUMBERS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Exercise|129 Videos
  • COMPLEX NUMBERS

    OBJECTIVE RD SHARMA ENGLISH|Exercise Chapter Test|58 Videos
  • CIRCLES

    OBJECTIVE RD SHARMA ENGLISH|Exercise Chapter Test|53 Videos
  • CONTINUITY AND DIFFERENTIABILITY

    OBJECTIVE RD SHARMA ENGLISH|Exercise Exercise|87 Videos

Similar Questions

Explore conceptually related problems

(v) |(z_1)/(z_2)|=|z_1| /|z_2|

If for the complex numbers z_1 and z_2 , |z_1+z_2|=|z_1-z_2| , then Arg(z_1)-Arg(z_2) is equal to

If |z_1+z_2|=|z_1-z_2| and |z_1|=|z_2|, then (A) z_1=+-iz_2 (B) z_1=z_2 (C) z_=-z_2 (D) z_2=+-iz_1

if |z_1+z_2|=|z_1|+|z_2|, then prove that a r g(z_1)=a r g(z_2) if |z_1-z_2|=|z_1|+|z_2|, then prove that a r g(z_1)=a r g(z_2)=pi

If z_1=2-i ,z_2=1+i , find |(z_1+z_2+1)/(z_1-z_2+i)|

If z_1=2-i ,z_2=1+i , find |(z_1+z_2+1)/(z_1-z_2+i)|

Which of the following is correct for any tow complex numbers z_1a n dz_2? (a) |z_1z_2|=|z_1||z_2| (b) a r g(z_1z_2)=a r g(z_1)a r g(z_2) (c) |z_1+z_2|=|z_1|+|z_2| (d) |z_1+z_2|geq|z_1|+|z_2|

If A (z_1), B (z_2) and C (z_3) are three points in the argand plane where |z_1 +z_2|=||z_1-z_2| and |(1-i)z_1+iz_3|=|z_1|+|z_3|-z_1| , where i = sqrt-1 then

If z_1=2-i ,\ z_2=1+i , find |(z_1+z_2+1)/(z_1-z_2+i)| .

If z_1=2-i ,\ z_2=1+i , find |(z_1+z_2+1)/(z_1-z_2+i)|

OBJECTIVE RD SHARMA ENGLISH-COMPLEX NUMBERS -Section I - Solved Mcqs
  1. If one root of z^2 + (a + i)z+ b +ic =0 is real, where a, b, c in R , ...

    Text Solution

    |

  2. If A and B represent the complex numbers z(1) and z(2) such that |z(1)...

    Text Solution

    |

  3. If z1ne-z2 and |z1+z2|=|1/z1 + 1/z2| then :

    Text Solution

    |

  4. Let O, A, B be three collinear points such that OA.OB=1. If O and B re...

    Text Solution

    |

  5. If z(0),z(1) represent points P and Q on the circle |z-1|=1 taken in a...

    Text Solution

    |

  6. The center of a square ABCD is at the origin and point A is reprsented...

    Text Solution

    |

  7. The value of k for which the inequality | Re (z) | + | Im (z)| leq l...

    Text Solution

    |

  8. The value of lambda for which the inequality |z(1)/|z(1)|+z(2)/|z(2)||...

    Text Solution

    |

  9. If z1a n dz2 both satisfy z+ z =2|z-1| and a r g(z1-z2)=pi/4 , then f...

    Text Solution

    |

  10. If z satisfies |z+1|lt|z-2|, then v=3z+2+i satisfies:

    Text Solution

    |

  11. If z complex number satisfying |z-1| = 1, then which of the followin...

    Text Solution

    |

  12. If z(1),z(2),z(3) are the vertices of an isoscles triangle right angle...

    Text Solution

    |

  13. Show that all the roots of the equation a(1)z^(3)+a(2)z^(2)+a(3)z+a(4)...

    Text Solution

    |

  14. If |z-1|=1, where z is a point on the argand plane, show that(z-2)/(z)...

    Text Solution

    |

  15. Let z be a non-real complex number lying on |z|=1, prove that z=(1+i...

    Text Solution

    |

  16. If |z|=2 and locus of 5z-1 is the circle having radius a and z1^2+z2^2...

    Text Solution

    |

  17. If |z+barz|+|z-barz|=8, then z lies on

    Text Solution

    |

  18. If a point z(1) is the reflection of a point z(2) through the line b b...

    Text Solution

    |

  19. If z is a complex number satisfying |z^(2)+1|=4|z|, then the minimum v...

    Text Solution

    |

  20. If z(1) and z(2) are two complex numbers satisying the equation. |(i...

    Text Solution

    |