AP EAMCET202421 May 2024Morning ShiftMathematicsComplex NumberActual
If is the cube root of unity a+b +c ^2 c+a +b ^2 + a+b +c ^2 b+c +a ^2 =
Options
- A2
- B-2
- C1
- D-1
Correct answer
D. -1
Step-by-step solution
aligned & a+b +c ^2 c+a +b ^2 + a+b +c ^2 b+c +a ^2 & a+b +c ^2 c+a +b ^2 + ^2 (a+b +c ^2 ) b ^2+c+a & = (1+ ^2 ) ( a+b +c ^2 c+a +b ^2 )=- (a +b ^2+c ) (c+a +b ^2 ) =-1 aligned