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Graphing y = log(0.3)^x-1

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The graph:

from to

Intersection points:

does show?

Piecewise:

The solution

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f(x) = log (3/10) - 1
$$f{\left(x \right)} = \log{\left(\frac{3}{10} \right)}^{x} - 1$$
f = log(3/10)^x - 1
The graph of the function
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:
$$\log{\left(\frac{3}{10} \right)}^{x} - 1 = 0$$
Solve this equation
The points of intersection with the axis X:

Analytical solution
$$x_{1} = 0$$
Numerical solution
$$x_{1} = 0$$
The points of intersection with the Y axis coordinate
The graph crosses Y axis when x equals 0:
substitute x = 0 to log(3/10)^x - 1.
$$-1 + \log{\left(\frac{3}{10} \right)}^{0}$$
The result:
$$f{\left(0 \right)} = 0$$
The point:
(0, 0)
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
$$\left(\log{\left(- \log{\left(\frac{3}{10} \right)} \right)} + i \pi\right) \log{\left(\frac{3}{10} \right)}^{x} = 0$$
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
$$\left(\log{\left(- \log{\left(\frac{3}{10} \right)} \right)} + i \pi\right)^{2} \log{\left(\frac{3}{10} \right)}^{x} = 0$$
Solve this equation
Solutions are not found,
maybe, the function has no inflections
Horizontal asymptotes
Let’s find horizontal asymptotes with help of the limits of this function at x->+oo and x->-oo
Limit on the left could not be calculated
$$\lim_{x \to -\infty}\left(\log{\left(\frac{3}{10} \right)}^{x} - 1\right)$$
Limit on the right could not be calculated
$$\lim_{x \to \infty}\left(\log{\left(\frac{3}{10} \right)}^{x} - 1\right)$$
Inclined asymptotes
Inclined asymptote can be found by calculating the limit of log(3/10)^x - 1, divided by x at x->+oo and x ->-oo
Limit on the left could not be calculated
$$\lim_{x \to -\infty}\left(\frac{\log{\left(\frac{3}{10} \right)}^{x} - 1}{x}\right)$$
Limit on the right could not be calculated
$$\lim_{x \to \infty}\left(\frac{\log{\left(\frac{3}{10} \right)}^{x} - 1}{x}\right)$$
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:
$$\log{\left(\frac{3}{10} \right)}^{x} - 1 = -1 + \log{\left(\frac{3}{10} \right)}^{- x}$$
- No
$$\log{\left(\frac{3}{10} \right)}^{x} - 1 = 1 - \log{\left(\frac{3}{10} \right)}^{- x}$$
- No
so, the function
not is
neither even, nor odd