Writing formulas and equations for some publication or websites is time consuming task. Usually there is LaTex syntax used to enter formulas. But when formulas get more complex it gets really hard to remember all short-codes and it is easy to loose end in a long line. At school we are used to write equations by hand so why not to transfer that experience in to computer.
We recommend EasyEDA for circuit design and PCB prototype
Here is a nice small script that simply converts hand written equation in to LaTex and MathML XML codes. All you have is to open a MyScript demo website and start drawing. Algorithm analyzes hand drawn formulas and tries to convert them in to code. It previews your progress so you could redo last steps to match your needs. I should say it does job really great. So if you do lots of formulas you may give a try – could be faster than typing.