Home
Class 12
MATHS
Let omega ne 1 be cube root of unity. Su...

Let `omega ne 1` be cube root of unity. Suppose `(1 + omega)^(2023) = A + B omega` where A, B `in` R, then `|A + Bi|^(2)` is equal to ______________.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the value of \(|A + Bi|^2\) where \((1 + \omega)^{2023} = A + B\omega\) and \(\omega\) is a cube root of unity. ### Step-by-Step Solution: 1. **Understanding Cube Roots of Unity**: The cube roots of unity are given by the equation \(x^3 = 1\). The roots are \(1, \omega, \omega^2\) where \(\omega = e^{2\pi i/3}\) and \(\omega^2 = e^{-2\pi i/3}\). They satisfy the relation: \[ 1 + \omega + \omega^2 = 0 \] Hence, we can express \(\omega^2\) as: \[ \omega^2 = -1 - \omega \] 2. **Expressing \(1 + \omega\)**: We know that: \[ 1 + \omega = -\omega^2 \] 3. **Calculating \((1 + \omega)^{2023}\)**: We can rewrite: \[ (1 + \omega)^{2023} = (-\omega^2)^{2023} = (-1)^{2023} (\omega^2)^{2023} \] Since \(2023\) is odd, \((-1)^{2023} = -1\). Thus, \[ (1 + \omega)^{2023} = -(\omega^2)^{2023} \] 4. **Using the properties of \(\omega\)**: We know that \(\omega^3 = 1\), so: \[ (\omega^2)^{2023} = \omega^{4046} = \omega^{4046 \mod 3} = \omega^{1} = \omega \] Therefore, \[ (1 + \omega)^{2023} = -\omega \] 5. **Setting up the equation**: We have: \[ (1 + \omega)^{2023} = A + B\omega \] Equating both sides gives: \[ -\omega = A + B\omega \] This implies: \[ A = 0 \quad \text{and} \quad B = -1 \] 6. **Finding \(|A + Bi|^2\)**: Now we need to calculate: \[ |A + Bi|^2 = |0 - i|^2 = | -i |^2 = |i|^2 \] The modulus of \(i\) is \(1\), so: \[ |i|^2 = 1^2 = 1 \] ### Final Answer: \[ |A + Bi|^2 = 1 \]
Promotional Banner

Topper's Solved these Questions

  • COMPLEX NUMBERS

    MCGROW HILL PUBLICATION|Exercise QUESTIONS FROM PREVIOUS YEARS. AIEEE/JEE MAIN PAPERS|58 Videos
  • COMPLEX NUMBERS

    MCGROW HILL PUBLICATION|Exercise QUESTIONS FROM PREVIOUS YEARS. B-ARCHITECTURE ENTRANCE EXAMINATION PAPER|17 Videos
  • COMPLEX NUMBERS

    MCGROW HILL PUBLICATION|Exercise EXERCISE LEVEL 21|1 Videos
  • CIRCLES AND SYSTEMS OF CIRCLES

    MCGROW HILL PUBLICATION|Exercise QUESTIONS FROM PREVIOUS YEARS. B-ARCHITECTURE ENTRANCE EXAMINATION PAPERS|17 Videos
  • DEFINITE INTEGRALS

    MCGROW HILL PUBLICATION|Exercise Questions from Previous Years. B-Architecture Entrance Examination Papers|18 Videos

Similar Questions

Explore conceptually related problems

If omega ne 1 is a cube root of unity, then 1, omega, omega^(2)

Let omega(omega ne 1) is a cube root of unity, such that (1+omega^(2))^(8)=a+bomega where a, b in R, then |a+b| is equal to

If omega (ne 1) is a cube root of unity and (1 + omega)^(2017) = A + B omega . Then A and B are respectively the numbers

If omega (ne 1) is a cube root of unity and (1 + omega^(2))^(11) = a + b omega + c omega^(2) , then (a, b, c) equals

If omega(ne 1) be a cube root of unity and (1+omega)^(7)=A+Bomega , then A and B are respectively the numbers.

MCGROW HILL PUBLICATION-COMPLEX NUMBERS -EXERCISE NUMERICAL ANSWER TYPE QUESTIONS
  1. Suppose a in R and z in C. "If" |z| = 2 and (z-alpha)/(z+alpha) is pur...

    Text Solution

    |

  2. If alpha an d beta are roots of the equation x^(2)-2x+2=0, then the le...

    Text Solution

    |

  3. Let S = {(2alpha+3i)/(2alpha-3i):alpha in R}. All the points of S lie ...

    Text Solution

    |

  4. Let omega ne 1 be cube root of unity. Suppose (1 + omega)^(2023) = A +...

    Text Solution

    |

  5. If (7+i)(z + bar(z))-(4+i)(z-bar(z)) + 116i = 0 then z bar(z) is equal...

    Text Solution

    |

  6. Let C(1) be the curve represented by (2z + i)/(z-2) is purely imaginar...

    Text Solution

    |

  7. Let a = 3 + 4i, z(1) and z(2) be two complex numbers such that |z(1)| ...

    Text Solution

    |

  8. Let alpha be the real and beta, gamma be the complex roots of x^(3) + ...

    Text Solution

    |

  9. Let z = ((2)/(i + sqrt(3)))^(200)+((2)/(i-sqrt(3)))^(200),"then" |z + ...

    Text Solution

    |

  10. Let z be a non-zero complex number such that area of the triangle with...

    Text Solution

    |

  11. Suppose x, y in R. If x^(2) + y + 4i is conjugate of -3 + x^(2) yi, th...

    Text Solution

    |

  12. All the roots of the equation x^(11) - x^(6) - x^(5) + 1 = 0 lie on a ...

    Text Solution

    |

  13. If 13 e^(i tan^(-1)(5//12))= a+ib, then |a| + |b| is equal to .

    Text Solution

    |

  14. Suppose, a, b, c ge 0, c ne 1, a^(2) + b^(2) + c^(2) = c. If |(a+ib)/(...

    Text Solution

    |

  15. Let z(1), z(2), z(3) be the roots of iz^(3) + 5z^(2) - z + 5i = 0, the...

    Text Solution

    |

  16. Let S = {z in C : z^(2) = 4 (i bar(z))^(2)},"then" sum(z in S)|z+(1)/(...

    Text Solution

    |

  17. Let z = (1)/(2) (sqrt(3) + i),"then" |(z^(101)+i^(103))^(105)|= .

    Text Solution

    |

  18. If alpha = cos((8pi)/11)+i sin ((8pi)/11) then Re(alpha + alpha^2+alph...

    Text Solution

    |

  19. Eccentricity of conic |z - 5i| + |z + 5i| = 25 is .

    Text Solution

    |

  20. If alpha is a non-real root of x^6=1 then (alpha^5+alpha^3+alpha+1)/(a...

    Text Solution

    |