Why Does the Integration of exp[abs(x)+3]*delta(x-2) from -1 to 1 Equal Zero?

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Homework Statement



Integrate exp[abs(x)+3]*delta(x-2) dx, -1, 1

2. The attempt at a solution

f(x)=exp[abs(x)+3]*delta(x-2)
f(2)=148.4
Integrate exp[abs(x)+3]*delta(x-2) dx, -1, 1 = 0

3. Why is the answer 0?
 
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NeedPhyHelp said:

Homework Statement



Integrate exp[abs(x)+3]*delta(x-2) dx, -1, 1

2. The attempt at a solution

f(x)=exp[abs(x)+3]*delta(x-2)
f(2)=148.4
Integrate exp[abs(x)+3]*delta(x-2) dx, -1, 1 = 0

3. Why is the answer 0?

Because the point x=2 does not lie in your domain of integration and your integrand vanishes at every other point.
 
Note that dirac delta function is zero if its argument is nonzero. The integration interval <-1;1> does not contain point x=2, where the dirac delta function is only nonzero.
 
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