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$$
(\gamma _{1}*\gamma _{2})(t)={\begin{cases}\gamma _{1}(2t)&{\textrm  {if\$0\leq t\leq 1/2\$}}\\\gamma _{2}(2t-1)&{\textrm  {if\$1/2\leq t\leq 1\$}}\end{cases}}
$$
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