Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
BITSAT2013MathematicsComplex NumberActual

If the real part of z +2 z -1 is 4, z 1, then the locus of the point representing z in the complex plane is

Options

  1. Aa straight line parallel to x -axis
  2. Ba straight line equally inclined to axes
  3. Ca circle with radius 2
  4. Da circle with radius 1 2

Correct answer

D. a circle with radius 1 2

Step-by-step solution

Real part of z +2 z -1 is given by array l 1 2 [ z +2 z -1 + ( z +2 z -1 ) ]=4 z +2 z -1 + z+2 z-1 =8 z z - z +2 z-2+z z +2 z -z-2 =8(z z - z -z+1) z z - 3 2 z- 3 2 z +2=0 array Comparing with the equation z z + a z+a z +b=0, we get a=- 3 2 and b=2 . Thus, the locus of z given by the equation (i) is a circle with centre = 1 2

Practice Complex Number on Quantrex Academy →

More from Complex Number

The points represented by the complex number 1+i,-2+3 i, 5 3 i on the argand plane are 2024The modulus of the complex number z such that |z+3-i|=1 and (z)= is equal to 2024If z, z ,-z,- z forms a rectangle of area 2 3 square units, then one such z is 2024If z₁, z₂, . . z_n are complex numbers such that |z₁ |= |z₂ |= . .= |z_n |=1 , then |z₁+z₂+ . .+z_n | is equal to 2024If |z₁ |=2, |z₂ |=3, |z₃ |=4 and |2 z₁+3 z₂+4 z₃ |= 4 , then absolute value of 8 z₂ z₃+27 z₃ z₁+64 z₁ z₂ equals 2024The modulus of (1+i 3 )(2+2 i) ( 3 -i) is 2023i⁵⁷+ 1 i²⁵ , when simplified has the value 2023If |w|=2 , then the set of points z=w- 1 w is contained in or equal to the set of points z satisfying 2022 Full Complex Number list All BITSAT PYQs