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linq - Filtering Null values in Select

I have IQueryable list of objects of type T which I want to transform into objects of type K

List<K> tranformedList = originalList.Select(x => transform(x)).ToList();

the transform function returns null if it cannot tranform the objects.If I want to filter out null elements can I call

List<K> tranformedList = originalList.Select(x => transform(x))
                                     .Where(y => y != default(K))
                                     .ToList();

or is there any other way of filtering out null elements when calling Select in LINQ ?

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Can't you just do something like this:

List<K> tranformedList = originalList.Select(x => tranform(x))
                                 .Where(y => y != null) //Check for nulls
                                 .ToList();

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