AP EAMCET202120 Aug 2021Evening ShiftMathematicsComplex NumberActual
What is the value of ( 1 - i 3 ) 9 =
Options
- A2 9
- B- 2 9
- C2 9 i
- D- 2 9 i
Correct answer
B. - 2 9
Step-by-step solution
Given: 1 - i 3 9 = 2 9 1 - i 3 2 9 = 2 9 1 2 - i 3 2 9 = 2 9 cos π 3 - i sin π 3 9 As we know ,   cos θ ± i sin θ n =   cos n θ ± i sin n θ = 2 9 cos 3 π - isin 3 π = - 2 9