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Which graph represents the function of f(x) = the quantity of 4 x squared minus 4 x minus 8, all over 2 x plus 2?

graph of 2 x minus 4, with discontinuity at negative 1, negative 6
graph of 2 x minus 4, with discontinuity at 1, negative 2
graph of 2 x plus 2, with discontinuity at negative 1, 0
graph of 2 x plus 2, with discontinuity at 1, 4

its not b. PLEASE SOMEONE HELP ME THANK YOU!!

User Xanco
by
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2 Answers

2 votes

Answer: D: 2 x minus 4, with discontinuity at negative 1, negative 6

Explanation:

User Andrey Kamaev
by
6.1k points
6 votes

we know that

the expression represent the function


f(x)=(4x^2-4x-8)/(2x+2)

Factor
4 in the numerator

Factor
2 in the denominator

so


f(x)=(4(x^2-x-2))/(2(x+1))

the domain of the function is all real numbers except for
x=-1 because the denominator can not be zero

Simplify the function


f(x)=(4(x^2-x-2))/(2(x+1))=(4(x+1)(x-2))/(2(x+1))


f(x)=2(x-2)=2x-4

Remember that for
x=-1 the function does not exist

so

find the value of f(x) for
x=-1 in the simplified function


f(x)=2x-4


f(-1)=2*(-1)-4=-6

The function has a discontinuity at point
(-1,-6)

therefore

the answer is the option

graph of 2 x minus 4, with discontinuity at negative 1, negative 6


User Melomg
by
6.0k points