Hi karthik143,
You can group by "Cust Account" and show max of Date, please refer to this msdn article msdn.microsoft.com/.../hh745337.aspx it explains how to use group by and aggregation like count in AOT query. Instead of count you need to use max, but idea is the same.
This one https://msddax.wordpress.com/2014/06/27/using-group-by-and-aggregate-function-in-execute-query-method-of-form-datasource/ explains how to do it in executeQuery() method.