If a +1 = 1, then the value of a3 is :a

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If a + 1 = 1, then the value of a³ is :
a

1. – 2
2. 2
3. – 1
4. 4

Correct Option: C

from the given question,

a +	1	= 1
	a

a² + 1 = a
a² + 1 - a = 0
Multiplying both side by (a + 1) and we will get,
(a + 1) (a² – a + 1) = 0 x ( a + 1 )
a x (a² – a + 1) + 1 x (a² – a + 1) = 0 x ( a + 1 )
a³ - a² + a + a² - a + 1 = 0
a³ + 1 = 0
a³ = –1