The event \(A\) of

getting two heads or two tails

in an experiment involving a sequence of

two flips of a fair coin

is the set

\begin{equation*} A = \{ (\mathrm{H}, \mathrm{H}), (\mathrm{T}, \mathrm{T}) \}, \end{equation*}

where	\(\mathrm{H}\)	is a symbol denoting “heads”
	\(\mathrm{T}\)	is a symbol denoting “tails”.