If x2 - 3x - 8x + 1 = 0, then the value of x3 + 1 is x3

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If x² - 3x - 8x + 1 = 0, then the value of x³ + 1 is
x³

1. 9
2. 18
3. 27
4. 1

Correct Option: B

Using Rule 8,
x² – 3x + 1 = 0
⇒ x² + 1 = 3x

⇒ x +	1	= 3
	x

∴ x³ +

1

=

x +

1

³

- 3 × x ×

1

x +

1

x³

x

x

x

= 27 – 3 × 3 = 18