Integration using exponentials

[g.lemaitre]

Homework Statement

the integral table says when you have the above form this will be the answer:

Homework Equations

The Attempt at a Solution

I looked at the integral table here

http://integral-table.com/integral-table.html#SECTION00006000000000000000

and it says erf - I don't know what that means. In any case the erf x√a does not appear in the answer. I also don't understand the step

A√(λ/π) = A = √λ/π

I also don't see why there is no two in the denominator.

 

[Ray Vickson]

Homework Statement

the integral table says when you have the above form this will be the answer:

Homework Equations

The Attempt at a Solution

I looked at the integral table here

http://integral-table.com/integral-table.html#SECTION00006000000000000000

and it says erf - I don't know what that means. In any case the erf x√a does not appear in the answer. I also don't understand the step

A√(λ/π) = A = √λ/π

I also don't see why there is no two in the denominator.

The definition of erf(x) IS include in the table.

RGV

 

[g.lemaitre]

Why is there no 2 in the denominator. I still don't know what erf means. I also don't understand the step

A√(λ/π) = A = √λ/π

 

[clamtrox]

http://en.wikipedia.org/wiki/Gaussian_integral

 

[clamtrox]

Why is there no 2 in the denominator.

Because the integral is from -∞ to ∞, not from 0 to ∞.

I still don't know what erf means.

It means "error function". Don't worry about that.

I also don't understand the step

A√(λ/π) = A = √λ/π

You are not reading it correctly, that's why. What it reads is
A√(π/λ) = 1
therefore
A = √λ/π

 

[g.lemaitre]

ok, thanks for the help.