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Which of the following is an x intercept of the function?

f(x)= x^3-5x^2-8x+48

A) 4
B) -4
C) 2
D) -2

User AnAmuser
by
7.8k points

2 Answers

2 votes

Answer:

A (4)

Explanation:

User Aritz
by
7.3k points
4 votes

Answer:

A) 4

Explanation:

The given function is
f(x)=x^3-5x^2-8x+48

If
f(a)=0, then
a is an x-intercept of
f(x)

Let us substitute x=4 and simplify:


f(4)=4^3-5(4)^2-8(4)+48


f(4)=64-80-32+48

This implies that:


f(4)=-48+48=0

Therefore 4 is an x-intercept of
f(x)=x^3-5x^2-8x+48

Also, f(-4)=64, f(2)=20, and f(-2)=36.

This means that, -4, 2, and -2 are not x-intercepts

User Pablobaldez
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7.9k points