JEE Main202127 Aug 2021Evening ShiftMathematicsComplex NumberActual
Let z 1 and z 2 be two complex numbers such that arg z 1 - z 2 = π 4 and z 1 , z 2 satisfy the equation z - 3 = Re ( z ) . Then the imaginary part z 1 + z 2 is equal to
Correct answer
0
Step-by-step solution
Let z 1 = x 1 + i y 1 , z 2 = x 2 + i y 2 z 1 - z 2 = x 1 - x 2 + i y 1 - y 2 ∵ arg z 1 - z 2 = π 4 ⇒ tan - 1 y 1 - y 2 x 1 - x 2 = π 4 ⇒ y 1 - y 2 = x 1 - x 2 - - - - ( 1 ) z 1 - 3 = Re z 1 ⇒ x 1 - 3 2 + y 1 2 = x 1 2 z 2 - 3 = Re z 2 ⇒ x 2 - 3 2 + y 2 2 = x 2 2 ⇒ x 1 - 3 2 - x 2 - 3 2 + y 1 2 - y 2 2 = x 1 2 - x 2 2 ⇒ x 1 - x 2 x 1 + x 2 - 6 + y 1 - y 2 y 1 + y 2 = x 1 + x 2 x 1 - x 2 ⇒ x 1 + x 2 - 6 + y 1 + y 2 = x 1 + x 2 ⇒ y 1 + y 2 = 6