diff --git a/.gitignore b/.gitignore
index 9245df6..32ca12a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,7 +5,6 @@
 *.fls
 *.log
 *.out
-*.pdf
 *.synctex.gz
 *.toc
 *.brf
diff --git a/algebra.pdf b/algebra.pdf
new file mode 100644
index 0000000..ace77d5
Binary files /dev/null and b/algebra.pdf differ