Question

If( x-a )is a factor of x^3-(a^2-1)x+2 find the value of a

Answer 1

Answer:

$question = (x - a) \: is \: a \: factor \: of \: {x}^{3} - ( {a}^{2} - 1)x + 2 \\ x - a = 0 \\ x = a \\ put \: x = a \: in \: the \: above \: equation \\ {a}^{3} - ( {a}^{2} - 1)a + 2 = 0 \\ {a}^{3} - ( {a}^{3} - a) + 2 = 0 \\ {a}^{3} - {a}^{3} + a + 2 = 0 \\ a + 2 = 0 \\ a = - 2$

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