MATHEMATICS

JAMB 2021 - Question 13

Mathematics 2021 JAMB Past Questions - Question 13: Find the value of k if y −1 is a factor of y³ + 4y² + ky − 6

Find the value of k if y −1 is a factor of y³ + 4y² + ky − 6
A:
B:
C:
D:
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Correct Answer

D

Explanation

To find the value of k if y - 1 is a factor of y³ + 4y² + ky - 6, we can use the factor theorem.According to the factor theorem, if y - 1 is a factor of the polynomial, then substituting y = 1 into the polynomial should result in zero.Let's substitute y = 1 into the polynomial y³ + 4y² + ky - 6:(1)³ + 4(1)² + k(1) - 6 = 1 + 4 + k - 6 = 5 + k - 6 = k - 1Since we want this expression to equal zero, we set k - 1 = 0 and solve for k:k - 1 = 0k = 1Therefore, the value of k is 1.