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2x −	1	= 5
	3x

On multiplying both sides by 3/2,

3x −	1	=	15
	2x		2

On cubing both sides,

27x³ −	1	−3.3x.	1
	8x³		2x

	3x −	1		=	3375
		2x			8

⇒ 27x³ −	1	−	9	×	15
	8x³		2		2

=	3375
	8

⇒ 27x³ −	1	=	3375	+	135
	8x³		8		4

=	3375 + 270	=	3645
	8		8

If 2x −	1	= 5, find the value of		27x³ +	1		.
	3x				8x³