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18. If 2 and 3 are the roots of x³ -3x² -4x + 12 = 0, what is the third root?

a. 1 b. -1 c. -2 d. -3​

User TrollBearPig
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1 Answer

17 votes
17 votes

Answer:

-2

Explanation:

p(x) = x³ - 3x² - 4x + 12

p(-2) = (-2)³ - 3 (-2)² -4(-2) + 12

= -8 - 3*4 + 8 + 12

= -8 - 12 + 8 + 12 = 0

(-2) is the root

User Richard Wheeldon
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