diff --git a/numerical_analysis/6/main.py b/numerical_analysis/6/main.py
index 67b0b3f..e08190e 100644
--- a/numerical_analysis/6/main.py
+++ b/numerical_analysis/6/main.py
@@ -8,7 +8,11 @@ from sklearn.preprocessing import PolynomialFeatures
 
 def f1(x, e):
     return math.exp(-x) * math.sin(x) \
-           + random.normalvariate(0, e ** 2)
+           + random.normalvariate(0, e)
+
+
+def f2(x, y, e):
+    return math.exp(-x ** 2 - y ** 2) * math.sin(x * y) + random.normalvariate(0, e)
 
 
 def solve1(x, y):