If x + 1 = 2 , then the value of x2 + 1x3 + 1 isxx2x3

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⇒ x +	1	= 2
	x

On squaring both sides,

⇒ x² +	1	+ 2 = 4
	x²

⇒ x² +	1	= 4 – 2 = 2
	x²

Again , x +	1	= 2
	x

On cubing both sides,

⇒		x +	1		³	= 8
			x

⇒ x³ +	1	+ 3		x +	1		= 8
	x³				x

⇒ x³ +	1	= 8 - 3 × 2 = 2
	x³

∴		x² +	1			x³ +	1		= 2 × 2 = 4
			x²				x³

Second Method :
Using Rule 14,

Here, x +	1	= 2
	x

x² +	1	= 2 and x³ +	1	= 2
	x²		x³

∴		x² +	1			x³ +	1		= 2 × 2 = 4
			x²				x³