Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • Engineering
  • I have a doubt, kindly clarify. - Matrices and Determinants - JEE Main

If 1,\omega ,\omega ^{2} are the cube roots of unity, then

  • Option 1)

    1

  • Option 2)

    \omega

  • Option 3)

    \omega ^{2}

  • Option 4)

    0

 

Answers (2)

best_answer

As we learnt in 

Value of determinants of order 3 -

-

 

 \Delta =\begin{vmatrix} 1 &\omega^{^{n}} &\omega^{2n} \\ \omega^{n} &\omega^{2n} &1 \\ \omega^{2n}&1 &\omega^{n} \end{vmatrix}

C_1 \rightarrow C_1+C_2+C_3

\Delta =\begin{vmatrix} 1+\omega^{^{n}} +\omega^{^{2n}} &\omega^{^{n}} &\omega^{2n} \\ 1+\omega^{^{n}} +\omega^{^{2n}} &\omega^{2n} &1 \\ 1+\omega^{^{n}} +\omega^{^{2n}}&1 &\omega^{n} \end{vmatrix}

for  n\epsilon N , 1+\omega^{^{n}} +\omega^{^{2n}}=0


Option 1)

1

Incorrect option

Option 2)

\omega

Incorrect option

Option 3)

\omega ^{2}

Incorrect option

Option 4)

0

Correct option

Posted by

Plabita

View full answer

Crack JEE Main with "AI Coach"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support
jee_ads

Similar Questions

Trending Articles/News

anam-khan

JEE Main 2023 Session 2: NTA adds exam dates; Check changes here
anam-khan

JEE Main 2023 City Intimation Slip (Out) Live: Session 2 admit card at jeemain.nta.nic.in soon, exam dates
anam-khan

JEE Main 2023 April Session: How e-libraries can help accelerate exam preparation

Latest Question