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Graphing y = x-2/(x-3)*(x+1)

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The graph:

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Intersection points:

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Piecewise:

The solution

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             2          
f(x) = x - -----*(x + 1)
           x - 3        
$$f{\left(x \right)} = x - \frac{2}{x - 3} \left(x + 1\right)$$
f = x - 2/(x - 3)*(x + 1)
The graph of the function
The domain of the function
The points at which the function is not precisely defined:
$$x_{1} = 3$$
The points of intersection with the X-axis coordinate
Graph of the function intersects the axis X at f = 0
so we need to solve the equation:
$$x - \frac{2}{x - 3} \left(x + 1\right) = 0$$
Solve this equation
The points of intersection with the axis X:

Analytical solution
$$x_{1} = \frac{5}{2} - \frac{\sqrt{33}}{2}$$
$$x_{2} = \frac{5}{2} + \frac{\sqrt{33}}{2}$$
Numerical solution
$$x_{1} = -0.372281323269014$$
$$x_{2} = 5.37228132326901$$
The points of intersection with the Y axis coordinate
The graph crosses Y axis when x equals 0:
substitute x = 0 to x - 2/(x - 3)*(x + 1).
$$- \frac{2}{-3}$$
The result:
$$f{\left(0 \right)} = \frac{2}{3}$$
The point:
(0, 2/3)
Extrema of the function
In order to find the extrema, we need to solve the equation
$$\frac{d}{d x} f{\left(x \right)} = 0$$
(the derivative equals zero),
and the roots of this equation are the extrema of this function:
$$\frac{d}{d x} f{\left(x \right)} = $$
the first derivative
$$1 - \frac{2}{x - 3} + \frac{2 \left(x + 1\right)}{\left(x - 3\right)^{2}} = 0$$
Solve this equation
Solutions are not found,
function may have no extrema
Inflection points
Let's find the inflection points, we'll need to solve the equation for this
$$\frac{d^{2}}{d x^{2}} f{\left(x \right)} = 0$$
(the second derivative equals zero),
the roots of this equation will be the inflection points for the specified function graph:
$$\frac{d^{2}}{d x^{2}} f{\left(x \right)} = $$
the second derivative
$$\frac{4 \left(1 - \frac{x + 1}{x - 3}\right)}{\left(x - 3\right)^{2}} = 0$$
Solve this equation
Solutions are not found,
maybe, the function has no inflections
Vertical asymptotes
Have:
$$x_{1} = 3$$
Horizontal asymptotes
Let’s find horizontal asymptotes with help of the limits of this function at x->+oo and x->-oo
$$\lim_{x \to -\infty}\left(x - \frac{2}{x - 3} \left(x + 1\right)\right) = -\infty$$
Let's take the limit
so,
horizontal asymptote on the left doesn’t exist
$$\lim_{x \to \infty}\left(x - \frac{2}{x - 3} \left(x + 1\right)\right) = \infty$$
Let's take the limit
so,
horizontal asymptote on the right doesn’t exist
Inclined asymptotes
Inclined asymptote can be found by calculating the limit of x - 2/(x - 3)*(x + 1), divided by x at x->+oo and x ->-oo
$$\lim_{x \to -\infty}\left(\frac{x - \frac{2}{x - 3} \left(x + 1\right)}{x}\right) = 1$$
Let's take the limit
so,
inclined asymptote equation on the left:
$$y = x$$
$$\lim_{x \to \infty}\left(\frac{x - \frac{2}{x - 3} \left(x + 1\right)}{x}\right) = 1$$
Let's take the limit
so,
inclined asymptote equation on the right:
$$y = x$$
Even and odd functions
Let's check, whether the function even or odd by using relations f = f(-x) и f = -f(-x).
So, check:
$$x - \frac{2}{x - 3} \left(x + 1\right) = - x - \frac{2 \left(1 - x\right)}{- x - 3}$$
- No
$$x - \frac{2}{x - 3} \left(x + 1\right) = x + \frac{2 \left(1 - x\right)}{- x - 3}$$
- No
so, the function
not is
neither even, nor odd