$ aspell -t -c filename

cdrecord

$ cdrecord -scanbus
$ cdrecord -v -eject speed=4 dev=0,2,0 -data file.iso

LaTeX

limit(1/(k*x)*(1-sqrt(1-k*x^2)),k=0,left);

Mathematica

Solve [t = a1 + a2*((t*(2*t - 3*a3))/6 + a3^3/(6*t)), t]
p = ...
Solve [{D[p, a1] == 0, D[p, a2] == 0, D[p, a3] == 0}, {a1, a2, a3}]

Matlab

>> syms a1 a2 a3 t
>> solve ('t = a1 + a2*((t*(2*t-3*a3))/6 + a3^3/(6*t))', 't')
>> p1 = diff(p, a1)
>> p2 = diff(p, a2)
>> p3 = diff(p, a3)
>> syms x y z
>> (x,y,z) = solve(p1,p2,p3)
>> [x,y,z] = solve(p1,p2,p3, 'a3 >= 0')

mkisofs

mkisofs -r -J -o file.iso directory/

mysql

Invoking mysql: mysql -h host -u user -p database_name This will prompt for a password.

To create a database: CREATE DATABASE database_name;

To use a database: USE database_name;

Tables: SHOW TABLES;, CREATE TABLE tbl_name (name VARCHAR(20), label CHAR(1));, DESCRIBE tbl_name;

Inserting: INSERT INTO tbl_name VALUES ('name','A');