Only one doubt.........?

Just tell me i think that parveen sharma,aaditya jain and other teachers like surbhi bansal and manish bhandari say in class or give us their notes,we should trust on them blindly,if we have little bit of doubt on any line or any thing which is told by teacher then we should clarify from others...but some my friends say dont trust on teacher blindly,check notes of these teachers(like questions,answers,concepts,all things which teacher say in class)from other faculty teachers... who is correct??????????