--- /dev/null
+## When m=1 we should agree with rosenbrock_hessian1().
+
+x = [4;5];
+f1 = rosenbrock_hessian1(x);
+f2 = extended_rosenbrock_hessian1(x);
+
+unit_test_equals("(extended_)rosenbrock_hessian1 agree for m=1", ...
+ true, ...
+ f1 == f2);