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Question
In the following problems use the factor theorem to find if g(x) is a factor of p(x):
p(x) = 2x3 + 4x + 6 and g(x) = x + 1
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Solution
p(x) = 2x3 + 4x + 6 and g(x) = x + 1
Now put x = -1 in equation (i), we get
p(-1) = 2(-1)3 + 4(-1) + 6
= 2 x - 1 - 4 + 6
= -2 - 4 + 6
= -6 + 6 = 0
Since, p(-1) = 0, so by factor theorem (x = 1) is a factor of p(x).
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