diff --git a/module2/exo1/toy_document_orgmode_R_fr.org b/module2/exo1/toy_document_orgmode_R_fr.org
index 419bb392d3f667a2bbf4b707965e2bb297afaf4c..260d8b9d6c62c5dd4e987480bfae57a5c0f52506 100644
--- a/module2/exo1/toy_document_orgmode_R_fr.org
+++ b/module2/exo1/toy_document_orgmode_R_fr.org
@@ -13,7 +13,7 @@
 
 Mon ordinateur m’indique que $\pi$ vaut /approximativement/
 
-#+begin_src R :results output :exports both
+#+begin_src R :results output :session *R* :exports both
 pi
 #+end_src
 
@@ -40,7 +40,7 @@ suivant illustre ce fait :
 set.seed(42)
 N = 1000
 df = data.frame(X = runif(N), Y = runif(N))
-df$Accept = (df$X**2 <=1=
+df$Accept = (df$X**2+ df$Y**2 <=1)
 library(ggplot2)
 ggplot(df, aes(x=X,y=Y, color=Accept)) + geom_point(alpha=.2) + coord_fixed() + theme_bw()
 #+end_src