diff --git a/tests/misc.rs b/tests/misc.rs
index 504b0bd..70abb58 100644
--- a/tests/misc.rs
+++ b/tests/misc.rs
@@ -152,7 +152,7 @@ fn newtons_method() {
 
     let data = newtons_method(
         &get_flatexwrapper("x^2 -1"),
-        &get_flatexwrapper("2x"),
+        &get_flatexwrapper("2*x"),
         3.0,
         &(0.0..5.0),
         f64::EPSILON,