Is f(x)δ(x) Equal to f(2)δ(x)?

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athrun200
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Homework Statement



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Homework Equations





The Attempt at a Solution



Can I write, say, [itex]f(x) \delta(x)=f(2)\delta(x)[/itex]?
Since [itex]\delta(x)[/itex] =0 for x[itex]\neq[/itex]0
 
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hunt_mat said:
I think you can say [itex]f(x)\delta (x-2)=f(2)\delta (x)[/itex]

Then if x=2, left hand side will become infinity and the right hand side 0.
Is it Ok?
 
athrun200 said:
So what's wrong with my post in #1?

The integral of [itex]f(x) \delta(x)[/itex] over x is f(0). The integral of [itex]f(2) \delta(x)[/itex] over x is f(2). So no, they aren't the same.