diff --git a/src/game/formulas/formulas.ts b/src/game/formulas/formulas.ts
index bf989b1..79adfce 100644
--- a/src/game/formulas/formulas.ts
+++ b/src/game/formulas/formulas.ts
@@ -124,11 +124,14 @@ export abstract class InternalFormula<T extends [FormulaSource] | FormulaSource[
 
         const innermostVariable = numVariables === 1 ? variable?.innermostVariable : undefined;
 
+        const invertible = variable?.isInvertible() ?? false;
+        const integrable = variable?.isIntegrable() ?? false;
+
         return {
             inputs,
             internalEvaluate: evaluate,
-            internalInvert: invert,
-            internalIntegrate: integrate,
+            internalInvert: invertible ? invert : undefined,
+            internalIntegrate: integrable ? integrate : undefined,
             internalIntegrateInner: integrateInner,
             applySubstitution,
             innermostVariable,
diff --git a/tests/game/formulas.test.ts b/tests/game/formulas.test.ts
index db020a5..462d3d8 100644
--- a/tests/game/formulas.test.ts
+++ b/tests/game/formulas.test.ts
@@ -491,10 +491,17 @@ describe("Inverting", () => {
         expect(formula.invert(100)).compare_tolerance(0);
     });
 
-    test("Inverting with non-invertible sections", () => {
-        const formula = Formula.add(variable, constant.ceil());
-        expect(formula.isInvertible()).toBe(true);
-        expect(formula.invert(10)).compare_tolerance(0);
+    describe("Inverting with non-invertible sections", () => {
+        test("Non-invertible constant", () => {
+            const formula = Formula.add(variable, constant.ceil());
+            expect(formula.isInvertible()).toBe(true);
+            expect(() => formula.invert(10)).not.toThrow();
+        });
+        test("Non-invertible variable", () => {
+            const formula = Formula.add(variable.ceil(), constant);
+            expect(formula.isInvertible()).toBe(false);
+            expect(() => formula.invert(10)).toThrow();
+        });
     });
 });
 
@@ -619,6 +626,19 @@ describe("Integrating", () => {
         const formula = Formula.pow(1.05, variable).times(100).pow(0.5);
         expect(() => formula.evaluateIntegral()).toThrow();
     });
+
+    describe("Integrating with non-integrable sections", () => {
+        test("Non-integrable constant", () => {
+            const formula = Formula.add(variable, constant.ceil());
+            expect(formula.isIntegrable()).toBe(true);
+            expect(() => formula.evaluateIntegral()).not.toThrow();
+        });
+        test("Non-integrable variable", () => {
+            const formula = Formula.add(variable.ceil(), constant);
+            expect(formula.isIntegrable()).toBe(false);
+            expect(() => formula.evaluateIntegral()).toThrow();
+        });
+    });
 });
 
 describe("Inverting integrals", () => {