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Question
Find the value of a , if (x - a) is a factor of x3 - a2x + x + 2.
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Solution
Let f(x) = x2 - a2x + x + 2
Put x - a = 0
∴ x = a
f(a) = a3 - a2·a + a + 2
0 = a3 - a3 + a + 2
or
a + 2 = 0
∴ a = -2
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