JEE Main201912 Apr 2019Evening ShiftMathematicsComplex NumberActual
Let z ∈ C with I m ( z ) = 10 and it satisfies 2   z - n 2   z + n = 2 i - 1 for some natural number n . Then
Options
- An = 20 and R e ( z ) = 10
- Bn = 40 and R e ( z ) = 10
- Cn = 20 and R e ( z ) = - 10
- Dn = 40 and R e ( z ) = - 10
Correct answer
D. n = 40 and R e ( z ) = - 10
Step-by-step solution
Put z = x + 10 i ∴ 2 x + 10 i - n = 2 i - 1 ⋅ 2 x + 10 i + n compare real and imaginary coefficients x = - 10 , n = 40