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If (x + 1) is a factor of 2x - kx²-8x + 5, find the value of k.
[ Using Factor Theorem ]​

User MatsLindh
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1 Answer

3 votes

Answer:

k = 11

Explanation:

What the factor theorem is telling us is that if x + 1 is a factor of 2x - kx²-8x + 5 then when x = - 1 is put into the equation, the result will be 0. That's because x +1 = 0 when x = - 1

f(-1) = 2(-1) - k(-1)^2 - 8(-1) + 5

f(-1) = -2 - k(1) + 8 + 5 = 0

-k*(1) + 11 = 0

-k = -11

k = 11

User Kemicofa Ghost
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