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Question
Prove that (x-3) is a factor of x3 - x2 - 9x +9 and hence factorize it completely.
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Solution
If x - 3 assumed to be factor, then x = 3. Substituting this in problem polynomial, we get:
f(3) = 3 × 3 × 3 - 3 × 3 - 9 × 3 + 9 = 0
Hence its proved that x - 3 is a factor of the polynomial.
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