\(
\def\lparen{(}
\def\rparen{)}
\def\apb{a+b}
\def\apbb{{a+b}}
\)
\begin{equation}
\lparen x^2 + 7 \rparen^2
\end{equation}
\begin{equation}
\big\lparen x^2 + 7 \big\rparen^2
\end{equation}
\begin{equation}
\bigl\lparen x^2 + 7 \bigr\rparen^2
\end{equation}
\begin{equation}
\big( x^2 + 7 \big)^2
\end{equation}
And for exponents:
\begin{equation}
T^(
\end{equation}
\begin{equation}
T^\lparen
\end{equation}
\begin{equation}
T^{\lparen}
\end{equation}
\begin{equation}
T^{\apb}
\end{equation}
\begin{equation}
T^\apb
\end{equation}
\begin{equation}
T^\apbb
\end{equation}