diff --git a/src/Grid.fs b/src/Grid.fs
index 12c7621..7ee6d05 100644
--- a/src/Grid.fs
+++ b/src/Grid.fs
@@ -429,7 +429,7 @@ module Util =
         let neg = (d1 <= 0.) || (d2 <= 0.) || (d3 <= 0.)
         let pos = (d1 >= 0.) || (d2 >= 0.) || (d3 >= 0.)
 
-        neg && pos |> not
+        (neg && pos) |> not
 
     let inline isInsideTriangle_dbl (x, y, z) p =
         let sign (p1x, p1y) (p2x, p2y) (p3x, p3y) =
@@ -443,7 +443,7 @@ module Util =
         let neg = (d1 <= 0.0) || (d2 <= 0.0) || (d3 <= 0.0)
         let pos = (d1 >= 0.0) || (d2 >= 0.0) || (d3 >= 0.0)
 
-        neg && pos |> not
+        (neg && pos) |> not
 
     // make a kd-tree for looking up nearest node
     let buildNearestNodeTree (grid: IGrid) =
@@ -670,4 +670,4 @@ type ExtendedGrid(grid: IGrid) =
             elementTree <- binarySerializer.UnPickle<IdxTree> pickle |> Some
             true
         else
-            false
+            false
\ No newline at end of file