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If A=[[2,3],[1,-2]] and A^-1=kA,then t...

If `A=[[2,3],[1,-2]]` and `A^-1=kA`,then
the value of 'k' is

A

7

B

-7

C

`1/7`

D

`-1/7`

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BODY BOOKS PUBLICATION-DETERMINANTS-EXERCISE
  1. Choose the correct answer from the bracket. If A=[(cosx,sinx),(-sinx,c...

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  2. Find the inverse of the following A=[[1,-1,2],[0,2,-3],[3,-2,4]]

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  3. If A=[[2,3],[1,-2]] and A^-1=kA,then the value of 'k' is

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  4. If A=[[1,-1,1],[2,-1,0],[1,0,0]], Find A^2

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  5. If A=[[1,-1,1],[2,-1,0],[1,0,0]], Show that A^2=A^-1

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  6. Choose the correct answer. If each element of a third order square mat...

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  7. Consider the matrix A=[(-8,5),(2,4)] Show that 'A' satisfies the equat...

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  8. Consider the matrix A=[(-8,5),(2,4)] Hence find A^-1.

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  9. If A and B are matrices of order 3 such that abs[A]=-1,abs[B]=3,then...

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  10. If A=[(1,tanx),(-tanx,1)], Show that, A^TA^-1=[(cos2x,-sin2x),(sin2x,c...

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  11. If A=[[1,1,5],[0,1,3],[0,-1,-2]] what is the value of abs[3A]?

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  12. Find the equation of the line joining the points(1,2) and (-3,-2) us...

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  13. Find the values of x in which abs[[3,x],[x,1]]=abs[[3,2],[4,1]]

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  14. Using the property of determinants,show that the points A(a,b+c),B(b...

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  15. Examine the consistency of system of following equations: 5x-6y+4z...

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  16. If A=[[3,-2,3],[2,1,-1],[4,-3,2]] Find abs[A]

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  17. If A=[[3,-2,3],[2,1,-1],[4,-3,2]] Find A^-1

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  18. If A=[[3,-2,3],[2,1,-1],[4,-3,2]] Solve the linear equations 3x-2y...

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