# Strange Error Message when Plotting with a LaTeX Legend

The following code is from the 1st edition of my textbook, *Sage for Undergraduates*. It is producing some extremely unexpected errors (technically, deprication warnings). Something about an invalid escape sequence, `\i`

, which I'm not using.

Can someone explain how I should change my code, so that these warnings do not appear?

Code:

`P1= text('$\int_0^2 \sqrt{x} \, dx$', (0.5, 1.1), fontsize=20)`

`P2= plot( sqrt(x), 0, 2, fill=True)`

`P= P1 + P2`

`P.show()`

Warning:
`<input>:1: DeprecationWarning: invalid escape sequence \i`

Quick Link: https://sagecell.sagemath.org/?z=eJwV...