NTA Abhyas JEE Main2020MathematicsComplex NumberPractice
If z 1 = 2 + 3 i , z 2 = 3 - 2 i and z 3 = - 1 - 2 3 i , then which of the following is true? (where, i 2 = - 1 )
Options
- Aa r g z 2 z 3 = a r g z 2 - z 1 z 3 - z 1
- Ba r g z 2 z 3 = a r g z 3 z 1
- C1 2 a r g z 2 z 3 = a r g z 2 - z 1 z 3 - z 1
- D2 a r g z 3 z 2 = a r g z 3 - z 1 z 2 - z 1
Correct answer
C. 1 2 a r g z 2 z 3 = a r g z 2 - z 1 z 3 - z 1
Step-by-step solution
Here, z 1 = z 1 = z 3 = 13 Hence, z 1 , z 2 , z 3 lie on a circle with center 0 , 0 and r = 13 as shown Now, a r g z 2 z 3 = 2 a r g z 2 - z 1 z 3 - z 1 ∴ a r g z 3 z 2 = 2 a r g z 3 - z 1 z 2 - z 1