# Weird 'Missing $inserted' The first screenshot is the formula. It is a part of my assignment. However, when I compile it, I got a lot of Missing$ inserted I cannot understand why. Thank you!

• Welcome to TeX.SX! Please do not paste code as images, but as code starting with \documentclass and ending with \end{document}. – Bobyandbob Nov 15 '17 at 10:19
• when you use equation comand, I think that there is no need $inside P/S next time write the code instead of using an image :) – mortal Nov 15 '17 at 10:20 • Don't use $ ...  constructs inside mathematical environments like equation, align, gather, &c. – Bernard Nov 15 '17 at 10:22 ## 1 Answer  shifts from text mode to math mode and back. starts math mode, R^i_t = is fine. Then \$ ends math mode and enters text mode. Then \alpha is used in text mode and you get an error.

So change

$$R^i_t = \alpha + \betaR^M_t + \mu_t$$


into

$$R^i_t = \alpha + \beta R^M_t + \mu_t$$