How do companies trust that the colleges you go are legitimate (legitimate as in the content they teach is well aligned)

This might sound confusing but if colleges are very different curriculums for courses like Calculus 1 or Calculus 2, how do you know they are teaching the same content. For all I know, one college could be teaching Algebra II disguised as "Calculus 2" while the other could be teaching Calculus 1 that has "Calculus 2" content. How do you even define what content is Calculus 1 and Calculus 2? (I am just using Calculus as an example but this could apply the same to many different classes like biology or general chemistry)