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Determine the value of m so that (x-2) is a factor of x^3 + 2mx^2 +6x -4.

User Ovicko
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1 Answer

4 votes
Answer:

m = -2

Step-by-step explanation:

The given function is:


f(x)=x^3+2mx^2+6x-4

For x - 2 to be a factor of f(x):

f(x) must be equal to zero when x = 2


\begin{gathered} f(2)=2^3+2m(2^2)+6(2)-4 \\ f(2)=8+8m+12-4 \\ f(2)=8m+16 \end{gathered}

Let f(2) = 0 to solve for m

8m + 16 = 0

8m = -16

m = -16/8

m = -2

Therefore, for x - 2 to be a factor of x^3 + 2mx^2 +6x -4, the value of m is -2

User Jamiey
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