flex-indexes.adoc small corrections (couchbase/docs-server#2699)

Correct array example and hint

Author: simon-dew

modules/n1ql/pages/n1ql-language-reference/flex-indexes.adoc

@@ -58,7 +58,7 @@ Some of the main differences are described here.
 
 * {sqlpp} uses escaped path names, whereas full-text indexes flatten the field names.
 
-* {sqlpp} uses array subscripts to identify array objects, for example `1.arr1[0].b`; whereas full-text indexes ignore subscripts, for example `f1.arr1.b`.
+* {sqlpp} uses array subscripts to identify array objects, for example `f1.arr1[0].b`; whereas full-text indexes ignore subscripts, for example `f1.arr1.b`.
 This means full-text indexes cannot uniquely identify the path.
 
 * In {sqlpp}, data can be compared across data types.
@@ -94,7 +94,7 @@ For further details, refer to {build-index}[BUILD INDEX].
 
 Assuming that there is no search function in the query predicate, there are two ways to specify that you would like to use a full-text index with a {sqlpp} query:
 
-* Use the `USE FTS` hint in the {sqlpp} query.
+* Use the `USING FTS` hint in the {sqlpp} query.
 For full details, refer to {index-type}[USE Clause].
 
 * Set the `use_fts` request-level parameter to `true`.