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




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

please and thank you

Verified Answer :

\(f(x) = \frac{4x^{2} - 4x - 8}{2x}\)
\(f(x) = \frac{4x^{2}}{2x} - \frac{4x}{2x} - \frac{8}{2x}\)
\(f(x) = 2x - 2 - \frac{4}{x}\)

\(x = 0\)

The answer is C.

Solution:

The given function is

f(x)= \(\frac{4 x^2- 4 x -8}{2 x}\)

f(x)= \(\frac{4 x^2}{2 x}-\frac{4 x}{2x} -\frac{8}{2x}\\\\ = 2 x -2 -\frac{4}{ x}\)

f(x)= 2 x - 2 - \(\frac{4}{x}\)

To find the points of Discontinuity

Put, f(x)=0

→ 2 x - 2 - \(\frac{4}{x}\)=0

→2 x² - 2 x - 4=0×x

→2 (x²-x-2)=0

→ x² - x -2=0

Splitting the middle term

→ x² - 2 x + x -2=0

→ x×(x-2)+ 1 × (x-2)=0

→ (x+1) (x-2)=0

Gives, x= -1, and x=2.

So, the graph represented by f(x)= \(\frac{4 x^2- 4 x -8}{2 x}\) is equal to f(x)= 2 x - 2 - \(\frac{4}{x}\) with points of Discontinuity at -1 and 2.