Home
Class 12
MATHS
Let n ge 2 be an integer, A=({:(cos((2pi...

Let `n ge 2` be an integer, `A=({:(cos((2pi)/(n)),sin((2pi)/(n)),0),(sin((2pi)/(n)),cos((2pi)/(n)),0),(0,0,1):})`
and I is the idnetity matrix of order 3. Then

A

`A^(n)=I " and " A^(n-1) ne I`

B

`A^(m) ne I` for any positive integer m

C

A is not invertible

D

`A^(m)=0` for a positive integer m

Text Solution

Verified by Experts

The correct Answer is:
A
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ALGEBRA

    CHHAYA PUBLICATION|Exercise WBJEE ARCHIVE 2015|5 Videos
  • ALGEBRA

    CHHAYA PUBLICATION|Exercise WBJEE ARCHIVE 2016|4 Videos
  • ALGEBRA

    CHHAYA PUBLICATION|Exercise WBJEE ARCHIVE 2013|5 Videos
  • ADJOINT AND INVERSE OF A MATRIX AND SOLUTION OF LINEAR SIMULTANEOUS EQUATIONS BY MATRIX METHOD

    CHHAYA PUBLICATION|Exercise ASSERTION-REASON TYPE|2 Videos
  • ARCHIVE

    CHHAYA PUBLICATION|Exercise JEE Advanced Archive|13 Videos

Similar Questions

Explore conceptually related problems

Evaluate : underset(n to oo)lim (1)/(n)[sin (pi/(2n))+sin((2pi)/(2n))+sin((3pi)/(2n))+…+ sin((npi)/(2n))]

If [(cos(2pi)/7,-sin(2pi)/7),(sin(2pi)/7, cos(2pi)/7)]^k=[(1,0 ),(0 ,1)] , then the least positive integral value of k is (a) 3 (b) 4 (c) 6 (d) 7

Knowledge Check

  • The least positive integer n such that ({:(cos""((pi)/(4)),sin""((pi)/(4))),(-sin""((pi)/(4)),cos""((pi)/(4))):})^n is an identity matrix of order 2 is

    A
    4
    B
    8
    C
    12
    D
    16
  • Let n be a fixed positive integer such that sin(pi/(2n))+cos(pi/(2n))=sqrtn/2 then

    A
    n=4
    B
    n=5
    C
    n=6
    D
    none of these
  • Similar Questions

    Explore conceptually related problems

    Find sin( (pi)/n)+sin ((3pi)/n)+sin ((5pi)/n)+…….. to n terms

    Evaluate: underset(n rarr infty)lim 1/n[sin (pi/(2n)) +sin((2pi)/(2n))+sin ((3pi)/(2n))+......+sin((npi)/(2n))]

    sin^(3)x +sin^(3)(x-(2pi)/3) +sin^(3)(x+(2pi)/3)=0

    Let A=[(0,1),(0,0)] , show that (aI+bA)^(n)=a^(n)I+na^(n-1)bA , where I is the identity matrix of order 2 and n in N .

    Prove that, int_(0)^(2pi)(xsin^(2n)x)/(sin^(2n)x+cos^(2n)x)dx=pi^(2) .

    Show that sin(pi/n)+sin (3pi/n)+sin (5pi/n)+….n terms=0