The first one is from bbclearningenglish.comThey don't mean exactly the same thing, no. Where are those sentences from, please?
Sentence 1 means the two exhibitions were equally provoking*. Sentence 2 means that they were both provoking but one may have been more provoking* than the other.1) It was as provoking an exhibition as the one before it.
2) It was a provoking exhibition,
aslike the one before it.