Hello! This is a very good question. As a matter of fact, both of these sentences mean exactly the same thing. The only difference is the time or situation in which you would use these different forms. The first form that uses て is the more common way to connect clauses together and is used in conversation and general writing. On the other hand, the second form which uses only the stem of the verb, is used primarily in academic or formal writing. They mean the exact same thing though. Hope this helps!