\starttext

\startlines
1: $a⁺$
2: ${a⁺}$
3: $\displaystyle a⁺$
4: $\displaystyle{a⁺}$
\stoplines

\startlines
1: $(1,0)$
2: ${(1,0)}$
3: $\displaystyle (1,0)$
4: $\displaystyle{(1,0)}$
\stoplines

\startlines
1: $1 \not= 0$
2: ${1 \not= 0}$
3: $\displaystyle 1 \not= 0$
4: $\displaystyle{1 \not= 0}$
\stoplines

\stoptext
