% for Aditya:

\starttext

\startformula
    \ln (1+x) = \mcframed[background=color,backgroundcolor=red,foregroundcolor=white,frame=off]{x - {\frac {x^2}{\frac{x^3}{\frac{x^3}{3}}}}} + \frac{x^3}{3}-\cdots.
\stopformula

\startformula
    \ln (1+x) = \mcframed{x - {\frac {x^2}{\frac{x^3}{\frac{x^3}{3}}}}} + \frac{x^3}{3}-\cdots.
\stopformula

\stoptext
