If x = 1 – √2 , the value ofx - 13 is : x

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If x = 1 – √2 , the value of x - 1 ³ is :
x

1. – 8
2. 8
3. 2√2
4. 1

Correct Option: B

x = 1 – √2
On multiplying and divided by ( 1 + √2 )

∴	1	=	1 × ( 1 + √2 )
	x		( 1 – √2 )( 1 + √2 )

= 1 – √2

∴		x -	1		³	= ( 1 – √2 + 1 + √2 )³
			x

= 2³ = 8