Integrate the function e^(x^2)

  • Thread starter Thread starter lost_math
  • Start date Start date
  • Tags Tags
    Function Integrate
lost_math
Messages
5
Reaction score
0

Homework Statement


Integrate the function e^(-x^2) with definite integrals -infinity to X


Homework Equations





The Attempt at a Solution



I know that the indefinite integral of this reduces to sqrt(pi), but don't know what to do with the definite integral. Is this a known result that I can simply plug in and use?What kind of substitution can I try? FYI- this is a variation of the CDF for a normally distributed function...
 
Physics news on Phys.org
lost_math said:

Homework Statement


Integrate the function e^(-x^2) with definite integrals -infinity to X

Impossible in terms of elementary functions. Why not look up the error function though?

EDIT: is X independent of x? I am unclear with your notation.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...

Similar threads

Back
Top