Foundation
Mathematics Foundation
Factor theorem
Question
If (x + 1) is a factor of the polynomial (2x2 + kx) then k = ?
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Solution
If (x + 1) is a factor of the polynomial, then the polynomial equals zero when x = – 1 (Factor Theorem).
Substitute x = – 1 into the polynomial and set it equal to zero:
2(− 1)2 + k(− 1) = 0
Simplify the equation:
2(1) − k = 0
2 − k = 0
Therefore, k = 2.
Final Answer: 2