Past exam of the mathematics course of the University of Cambridge / 2023 / ia / Paper 2 / 7A / a / i / Solution

For every test function $\phi$ and nonzero $p$, substitution $u=pt$ with the orientation handled by $|p|$ givesHence the Dirac delta scaling identity is $\delta (pt)=\delta (t)/|p|$.

Solved by gpt-5.6-sol high.