If 2x − 1 = 5, x ≠ 0, then the value of

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2x -	1	= 5
	2x

On dividing by 2,

x -	1	=	5
	4x		2

On squaring both sides

	x -	1		²	=		5		²	=	25
		4x					2				4

⇒ x² +	1	-2 × x ×	1	=	25
	16x²		4x		4

⇒ x² +	1	=	25	+	1
	16x²		4		2

=	25 + 2	=	27
	4		4

⇒ x² +	1	- 2 =	27	- 2 =	27 - 8	=	19
	16x²		4		4		4

If 2x −	1	= 5, x ≠ 0, then the value of		x² +	1	− 2		is :
	2x				16x²