If for a non–zero x, 3x2 + 5x + 3 = 0, then the value

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3x² + 5x + 3 = 0
⇒ 3x² + 3 = –5x

⇒	3x² + 3	= –5
	x

⇒ 3x +	3	= –5
	x

⇒ x +	1	= –	5
	x		3

On cubing both sides,

	x +	1		³	=		−5		³	=	−125
		x					3				27

⇒ x³ +	1	+ 3		x +	1		=	−125
	x³				x			27

⇒ x³ +	1	+ 3 ×	−5	=	−125
	x³		3		27

⇒ x³ +	1	=	−125	+ 5
	x³		27

=	−125 + 135	=	10
	27		27

If for a non–zero x, 3x² + 5x + 3 = 0, then the value of x³ +	1	is :
	x³

−		10
		27

−		2
		3