m\bma\bat\btr\bri\bix\bx-\b-b\bba\bas\bsi\bic\bc - matrixes in equations
D\bDE\bES\bSC\bCR\bRI\bIP\bPT\bTI\bIO\bON\bN
- initial text ((a_11 a_21) (a_12 a_22)) (b_1 b_2) final text
+ initial text ((_\ba_11 _\ba_21) (_\ba_12 _\ba_22)) (_\bb_1 _\bb_2) [sin s\bsi\bin\bn] final text
OpenBSD October 10, 2014 OpenBSD