diff --git a/src/dichotomie.ts b/src/dichotomie.ts
index 9c5ccc1fcafd678ddb61c6bc0bee8598a188cc2b..278390dcd0f7efd57e4b7c0042740a0119422c6f 100644
--- a/src/dichotomie.ts
+++ b/src/dichotomie.ts
@@ -521,7 +521,7 @@ export class Dichotomie extends Debug {
                 Math.abs(newStep) <= tolAct
                 && (
                     Math.abs(fb) < errorTol
-                    || Math.abs(fb / fc) < 1
+                    || Math.abs(fb - fc) < errorTol * 1E5
                 )
             ) {
                 return b; // Acceptable approx. is found