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Is x - 8 a factor of the function f(x) = -2x3 + 17x2 - 64? Explain.

User Juline
by
7.6k points

2 Answers

4 votes
x-8=0
x=8
f(8)=-2(8)^3 +17(8)^2 - 64
=-2(512) + 17(64) - 64
= -1024+1088-64
= -1024 -64+1088
= -1088+1088
=0

so, x-8 is a factor of the function f(x) = -2x3 +17x2 - 64

hope this helps!!!!!! ^_^_^


User Srikanth Chekuri
by
7.8k points
2 votes

we know that

If
(x-8) is a factor of the function
f(x)=-2x^(3)+17x^(2)-64

then


x=8 is a root of the function f(x)

therefore

For
x=8 the value of the function must be zero

Verify

Substitute the value of
x=8 in the function


f(8)=-2(8)^(3)+17(8)^(2)-64


f(8)=-2(512)+17(64)-64


f(8)=-1,024+1,088-64


f(8)=-1,088+1,088


f(8)=0

therefore

the answer is

Yes,
(x-8) is a factor of the function f(x)