Home
Class 12
MATHS
By using properties of determinants. Sho...

By using properties of determinants. Show that:(i) `|1a a^2 1bb^2 1cc^2|=(a-b)(b-c)(c-a)`(ii) `|1 1 1a b c a^3b^3c^3|=(a-b)(b-c)(c-a)(a+b+c)`

Text Solution

Verified by Experts

`|{:(1,a,a^(2)),(1,b,b^(2)),(1,c,c^(2)):}|=|{:(0,a-c,a^(2)-c^(2)),(0,b-c,b^(2)-c^(2)),(1,c,c^(2)):}|" "({:(R_(1)toR_(1)-R_(3)),(R_(2)toR_(2)-R_(3)):})`
`=(a-c)(b-c)|{:(0,a-c,a^(2)-c^(2)),(0,b-c,b^(2)-c^(2)),(1,c,c^(2)):}|`
`=(a-c)(b-c)|{:(0,a-c,a^(2)-c^(2)),(0,b-c,b^(2)-c^(2)),(1,c,c^(2)):}|`
(Expending along `C_(1)`)
` =-(c-a)(b-c)(b+c-a-c) `
`=-(b-c)(c-a)(b-a)`
`=(a-b)(b-c)(c-a)=R.H.S.`
(ii) `|{:(1,1,1),(a,b,c),(a^(3),b^(3),c^(3)):}|=|{:(0,0,1),(a-b,b-c,c),(a^(3)-b^(3),b^(3)-c^(3),c^(3)):}|" "({:(C_(1)toC_(1)-C_(2)),(C_(2)toC_(2)-C_(3)):})`
`=(a-b)(b-c)|{:(0,0,1),(1,1,c),(a^(2)+b^(2)+ab,b^(2)+c^(2)+cb,c^(3)):}|`
`=(a-b)(b-c).1|{:(1,1),(a^(2)+b^(2)+ab,b^(2)+c^(2)+bc):}|" "("Expenbding along "{R_(1))`
`=(a-b)(b-c)(b^(2)+c^(2)+bc-a^(2)-b^(2)-ab)`
`=(a-b)(b-c)[c^(2)-a^(2)+bc-ab]`
`=(a-b)(b-c)(b-c)[(c-a)(c+a)+b(c-a)]`
`=(a-b)(b-c)(c-a)(c+a+b)`
`=(a-b)(b-c)(c-a)(a+b+c)`
=R.H.S
Promotional Banner

Topper's Solved these Questions

  • DETERMINANTS

    NAGEEN PRAKASHAN ENGLISH|Exercise Exercise 4.3|5 Videos
  • DETERMINANTS

    NAGEEN PRAKASHAN ENGLISH|Exercise Exercise 4.4|5 Videos
  • DETERMINANTS

    NAGEEN PRAKASHAN ENGLISH|Exercise Exercise 4.1|8 Videos
  • Continuity and Differentiability

    NAGEEN PRAKASHAN ENGLISH|Exercise Miscellaneous Exercise|23 Videos
  • DIFFERENTIAL EQUATIONS

    NAGEEN PRAKASHAN ENGLISH|Exercise Miscellaneous Exercise|18 Videos

Similar Questions

Explore conceptually related problems

By using properties of determinants. Show that: (i) |[1,a, a^2],[ 1,b,b^2],[ 1,c,c^2]|=(a-b)(b-c)(c-a) (ii) |[1, 1, 1],[a, b, c],[ a^3,b^3,c^3]|=(a-b)(b-c)(c-a)(a+b+c)

Show that |[1,a,a^2],[1,b,b^2],[1,c,c^2]|=(a-b)(b-c)(c-a)

Using properties of determinants, show that |1 a a^2 -b c 1 b b^2 -c a 1 c c^2 -a b|=0

Prove that: |1a a^2-b c1bb^2-c a1cc^2-a b|=0

Using properties of determinant show that: |[1 , a , bc] , [1 , b , ca] , [1 , c , a b]|=(a-b)(b-c)(c-a)

By using properties of determinants. Show that: |[a^2+1,a b, a c],[ a b,b^2+1,b c],[c a, c b, c^2+1]|=(1+a^2+b^2+c^2)

Show that |[a ,b ,c],[ a^2,b^2,c^2],[bc, ca, ab]|=|[1, 1, 1],[a^2,b^2,c^2],[a^3,b^3,c^3]|=(a-b)(b-c)(c-a)(a b+b c+c a) .

Prove that =|1 1 1a b c b c+a^2a c+b^2a b+c^2|=2(a-b)(b-c)(c-a)

Prove that |[1,a,a^3],[1,b,b^3],[1,c,c^3]|=(a-b)(b-c)(c-a)(a+b+c)

Using properties of determinant, prove that |(2a, a-b-c, 2a), (2b, 2b, b-c-a), (c-a-b,2c,2c)|=(a+b+c)^(3) .

NAGEEN PRAKASHAN ENGLISH-DETERMINANTS-Exercise 4.2
  1. Using the property of determinants and without expanding in questions ...

    Text Solution

    |

  2. Using the property of determinants and without expanding in questions ...

    Text Solution

    |

  3. Using the property of determinants and without expanding, prove that |...

    Text Solution

    |

  4. Using the property of determinants and without expanding, prove that:...

    Text Solution

    |

  5. Using the property of determinants and without expanding, prove that:...

    Text Solution

    |

  6. Using the property of determinants and without expanding, prove that:...

    Text Solution

    |

  7. Using the property of determinants and without expanding, prove that:...

    Text Solution

    |

  8. By using properties of determinants. Show that:(i) |1a a^2 1bb^2 1cc^2...

    Text Solution

    |

  9. Using the properties of determinants, show that: [[x, x^2, yz],[y, y...

    Text Solution

    |

  10. By using properties of determinants. Show that: (i) |x+4 2x2x2xx+4 2x2...

    Text Solution

    |

  11. By using properties of determinants. Show that:(i) |a-b-c2a2a2bb-c-a2b...

    Text Solution

    |

  12. Using properties of determinants, prove the following: |1xx^2x^2 1...

    Text Solution

    |

  13. By using properties of determinants. Show that:|1+a^2-b^2 2a b-2b2a b1...

    Text Solution

    |

  14. Using properties of determinants, prove the following: |[a^2 + 1,ab, ...

    Text Solution

    |

  15. Let A be a square matrix of order 3xx3, then |k A|is equal to(A) k|A|...

    Text Solution

    |

  16. Which of the following is correct (A) Determinant is a square matrix. ...

    Text Solution

    |