Proving the Limit of a Parabola Delta Function

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SUMMARY

The forum discussion centers on proving the limit of a parabola delta function defined as L = lim (k→∞) ∫[-3/(4k), 3/(4k)] f(x)[-16k³/9 x² + k] dx = f(0). Participants argue that as k approaches infinity, the parabola becomes infinitely tall and narrow, converging to a delta function. The discussion also touches on the filtering property of the Dirac delta function and the implications of using different types of functions, such as continuous and differentiable functions, in this context.

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  • Understanding of limits in calculus
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  • Knowledge of definite integrals and the Mean Value Theorem
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  • #31
Looks good to me. :smile:

As long as f is continuous, and the area beneath the curves formed by each member in your sequence equals 1, then this argument really shows that ANY such sequence is good enough to represent the delta function(al).
 

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