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If |[x+1,x-1],[x-3,x+2]|=|[4,-1],[1,3]|, then write the value of x.

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Question

If `|[x+1,x-1],[x-3,x+2]|=|[4,-1],[1,3]|`, then write the value of x.

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Solution

`|[x+1,x-1],[x-3,x+2]|=|[4,-1],[1,3]|`

`(x+1)(x+2)-(x-1)(x-3)=12+1`

`x^2+3x+2-[x^2-4x+3]=13`

`7x-1=13`

x=2

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2012-2013 (March) Delhi Set 1

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