RootFinding: simple usage in F# module should try the same algorithms as core

src/FSharp/FindRoots.fs

@@ -69,8 +69,10 @@ module FindRoots =
 
     // simple usage
 
-    let ofFunction lowerBound upperBound (f:double->double) = brent 100 1e-8 lowerBound upperBound f
+    let ofFunction lowerBound upperBound (f:double->double) =
+        brent 100 1e-8 lowerBound upperBound f
+        |>| fun () -> bisection 100 1e-8 lowerBound upperBound f
 
     let ofFunctionAndDerivative lowerBound upperBound (f:double->double) (df:double->double) =
         newtonRaphsonRobust 100 20 1e-8 lowerBound upperBound f df
-        |>| fun () -> brent 100 1e-8 lowerBound upperBound f
+        |>| fun () -> bisection 100 1e-8 lowerBound upperBound f