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erf(x/sqrt(2))
  • How to use it?

  • Graphing y =:
  • erf(x/sqrt(2)) erf(x/sqrt(2))
  • log1/7*x
  • tanhx
  • tgx×ctgx tgx×ctgx
  • Identical expressions

  • erf(x/sqrt(two))
  • erf(x divide by square root of (2))
  • erf(x divide by square root of (two))
  • erf(x/√(2))
  • erfx/sqrt2
  • erf(x divide by sqrt(2))

Graphing y = erf(x/sqrt(2))

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The graph:

from to

Intersection points:

does show?

Piecewise:

The solution

You have entered [src]
          /  x  \
f(x) = erf|-----|
          |  ___|
          \\/ 2 /
$$f{\left(x \right)} = \operatorname{erf}{\left(\frac{x}{\sqrt{2}} \right)}$$
f = erf(x/(sqrt(2)))
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:
$$\operatorname{erf}{\left(\frac{x}{\sqrt{2}} \right)} = 0$$
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 erf(x/(sqrt(2))).
$$\operatorname{erf}{\left(\frac{0}{\sqrt{2}} \right)}$$
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
$$\frac{2 \frac{\sqrt{2}}{2} e^{- \frac{x^{2}}{2}}}{\sqrt{\pi}} = 0$$
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
$$- \frac{\sqrt{2} x e^{- \frac{x^{2}}{2}}}{\sqrt{\pi}} = 0$$
Solve this equation
The roots of this equation
$$x_{1} = 0$$

Сonvexity and concavity intervals:
Let’s find the intervals where the function is convex or concave, for this look at the behaviour of the function at the inflection points:
Concave at the intervals
$$\left(-\infty, 0\right]$$
Convex at the intervals
$$\left[0, \infty\right)$$
Horizontal asymptotes
Let’s find horizontal asymptotes with help of the limits of this function at x->+oo and x->-oo
$$\lim_{x \to -\infty} \operatorname{erf}{\left(\frac{x}{\sqrt{2}} \right)} = -1$$
Let's take the limit
so,
equation of the horizontal asymptote on the left:
$$y = -1$$
$$\lim_{x \to \infty} \operatorname{erf}{\left(\frac{x}{\sqrt{2}} \right)} = 1$$
Let's take the limit
so,
equation of the horizontal asymptote on the right:
$$y = 1$$
Inclined asymptotes
Inclined asymptote can be found by calculating the limit of erf(x/(sqrt(2))), divided by x at x->+oo and x ->-oo
$$\lim_{x \to -\infty}\left(\frac{\operatorname{erf}{\left(\frac{x}{\sqrt{2}} \right)}}{x}\right) = 0$$
Let's take the limit
so,
inclined coincides with the horizontal asymptote on the right
$$\lim_{x \to \infty}\left(\frac{\operatorname{erf}{\left(\frac{x}{\sqrt{2}} \right)}}{x}\right) = 0$$
Let's take the limit
so,
inclined coincides with the horizontal asymptote on the left
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:
$$\operatorname{erf}{\left(\frac{x}{\sqrt{2}} \right)} = - \operatorname{erf}{\left(\frac{\sqrt{2}}{2} x \right)}$$
- No
$$\operatorname{erf}{\left(\frac{x}{\sqrt{2}} \right)} = \operatorname{erf}{\left(\frac{\sqrt{2}}{2} x \right)}$$
- No
so, the function
not is
neither even, nor odd
The graph
Graphing y = erf(x/sqrt(2))