Verifying that a transaction is in the blockchain

Verifying that a transaction is in the blockchain

Let me first start off by saying im just learning about blockchain and the technical aspects.

From my understanding, each transaction is cryptographically hashed, the hashes are paired and hashed until a single root hash is generated. The miners hash the entire block containing the root hash, previous hash, timestamp etc. If the hash meets the target difficulty then the block is added to the chain. Cryptographic hashing makes it infeasible to obtain the input from the hash output.

Q. If say, I wanted to go back to block X and see which transactions it contains, how is that possible if all the hashes are cryptographic and its infeasible to find the input from the hash output?

Thanks in advance.

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