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

Domain:
V.A:
Roots:
Y-int:
H.A:
Holes:
O.A:

Also, draw on the graph attached.

f(x) = (x^(2) +4x-4)/(x^(2) -2x-8) Domain: V.A: Roots: Y-int: H.A: Holes: O.A: Also-example-1

1 Answer

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i) The given function is


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

We can rewrite in factored form to obtain;


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


f(x)=((x+2√(2)+2)(x-2√(2)+2))/((x-4)(x+2))

The domain is


(x-4)(x+2)\\e0


(x-4)\\e0,(x+2)\\e0


x\\e4,x\\e-2

ii) To find the vertical asymptotes equate the denominator to zero.


(x-4)(x+2)=0


(x-4)=0,(x+2)=0


x=4,x=-2

iii) To find the roots, equate the numerator to zero.


(x+2√(2)+2)(x-2√(2)+2)=0}


(x+2√(2)+2)=0,(x-2√(2)+2)=0}


(x=-2√(2)-2,x=2√(2)-2)}

iv) To find the y-intercept, substitute
x=0 into the equation.


f(0)=(0^2+4(0)-4)/(0^2-2(0)-8)

We simplify to obtain;


f(0)=(-4)/(-8)


f(0)=(1)/(2)

v) The horizontal asymptote is


lim_(\to \infty)(x^2+4x-4)/(x^2-2x-8)=1

The equation of the horizontal asymptote is y=1

vi) The function does not have a variable factor that is common to both the numerator and the denominator.

The function has no holes in it.

vii) The given function is a proper rational function.

Proper rational functions do not have oblique asymptotes.

f(x) = (x^(2) +4x-4)/(x^(2) -2x-8) Domain: V.A: Roots: Y-int: H.A: Holes: O.A: Also-example-1
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