Home
Class 12
MATHS
A square matrix P satisfies P^(2)=I-P, w...

A square matrix P satisfies `P^(2)=I-P`, where I is identity matrix. If `P^(n)=5I-8P`, then n is :

A

`4`

B

`5`

C

`6`

D

`7`

Text Solution

Verified by Experts

The correct Answer is:
C

`(c )` `P^(3)=P(I-P)=P-P^(2)=P-(I-P)=2P-1`
`P^(4)=P(2P-I)=2(I-P)-P=2I-3P`
`P^(5)=P(2I-3P)=2P-3(IP)=5P-3I`
`P^(6)=P(5P-3I)=5(I-P)-3P=5I-8P`
So `n=6`
Promotional Banner

Topper's Solved these Questions

  • MATHMETICAL REASONING

    CENGAGE PUBLICATION|Exercise Archives|10 Videos
  • METHODS OF DIFFERENTIATION

    CENGAGE PUBLICATION|Exercise Multiple Correct Answer Type|7 Videos

Similar Questions

Explore conceptually related problems

A square matrix M of order 3 satisfies M^(2)=I-M , where I is an identity matrix of order 3. If M^(n)=5I-8M , then n is equal to _______.

Let A=[("tan"pi/3,"sec" (2pi)/3),(cot (2013 pi/3),cos (2012 pi))] and P be a 2 xx 2 matrix such that P P^(T)=I , where I is an identity matrix of order 2. If Q=PAP^(T) and R=[r_("ij")]_(2xx2)=P^(T) Q^(8) P , then find r_(11) .

If A is a skew symmetric matrix, then B=(I-A)(I+A)^(-1) is (where I is an identity matrix of same order as of A )

Matrix A such that A^2=2A-I ,w h e r eI is the identity matrix, the for ngeq2. A^n is equal to 2^(n-1)A-(n-1)l b. 2^(n-1)A-I c. n A-(n-1)l d. n A-I

If P={:[(-1,3,5),(1,-3,-5),(-1,3,5)], show that, P^(2)=P hence find matrix Q such that 3P^(2)-2P+Q=I , where I is the unit matrix of order 3.

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 .

A square matrix A is used to be an idempotent matrix if A^(2) = A . If A is an idempotent matrix and B = I -A, then-

Show that the matrix A = {:[( 2,3),( 1,2) ]:} satisfies equation A^(2) -4A +I=0 where is 2xx2 identity matrix and O is 2xx2 Zero matrix. Using this equation, Find A^(-1)

If A is a square matrix such that A^2=A , then write the value of 7A-(I+A)^3, where I is the identity matrix.

Show that the matrix A=({:(2,-3),(3,4):}) satisfies the equation A^(2)-6A+17I=O and hence find A^(-1) where I is the identity matrix and O is the null matrix of order 2 times 2 .

CENGAGE PUBLICATION-MATRICES-All Questions
  1. If A=[{:(0,c,-b),(-c,0,a),(b,-a,0):}]and B=[{:(a^(2),ab,ac),(ab,b^(2),...

    Text Solution

    |

  2. If the value of prod(k=1)^(50)[{:(1,2k-1),(0,1):}] is equal to [{:(1,r...

    Text Solution

    |

  3. A square matrix P satisfies P^(2)=I-P, where I is identity matrix. If ...

    Text Solution

    |

  4. A and B are two square matrices such that A^(2)B=BA and if (AB)^(10)=A...

    Text Solution

    |

  5. If matrix A=[a(ij)](3xx3), matrix B=[b(ij)](3xx3), where a(ij)+a(ji)=0...

    Text Solution

    |

  6. If A({:(1,3,4),(3,-1,5),(-2,4,-3):})=({:(3,-1,5),(1,3,4),(+4,-8,6):}),...

    Text Solution

    |

  7. Let A=[{:(-5,-8,-7),(3,5,4),(2,3,3):}] and B=[{:(x),(y),(1):}]. If AB ...

    Text Solution

    |

  8. A=[{:(a,b),(b,-a):}] and MA=A^(2m), m in N for some matrix M, then whi...

    Text Solution

    |

  9. If A=[a(ij)](mxxn) and a(ij)=(i^(2)+j^(2)-ij)(j-i), n odd, then which ...

    Text Solution

    |

  10. If det, (A-B) ne 0, A^(4)=B^(4), C^(3) A=C^(3)B and B^(3)A=A^(3)B, the...

    Text Solution

    |

  11. If AB+BA=0, then which of the following is equivalent to A^(3)-B^(3)

    Text Solution

    |

  12. A,B,C are three matrices of the same order such that any two are symme...

    Text Solution

    |

  13. If A and P are different matrices of order n satisfying A^(3)=P^(3) an...

    Text Solution

    |

  14. Let A, B are square matrices of same order satisfying AB=A and BA=B th...

    Text Solution

    |

  15. The number of 2xx2 matrices A, that are there with the elements as rea...

    Text Solution

    |

  16. If the orthogonal square matrices A and B of same size satisfy detA+de...

    Text Solution

    |

  17. If A=[[cos theta , sin theta],[sin theta,-costheta]], B = [[1,0],[-1,1...

    Text Solution

    |

  18. Let A be a 3xx3 matrix given by A=(a(ij))(3xx3). If for every column v...

    Text Solution

    |

  19. Let A and B be two non-singular matrices such that A ne I, B^(3) = I...

    Text Solution

    |

  20. Let A be a 2xx3 matrix, whereas B be a 3xx2 amtrix. If det.(AB)=4, the...

    Text Solution

    |