Question

Lim of tan(x) as x approaches pi/2. It does not ask from either the + or - direction, just pi/2. The answer is 0, but i think it is DNE? Cause from the left, it is infinity and from the right, negative infinity

Answer 1

Yes, you are right, if it approaches from the left, the limit is infinity and if it approaches from the right, the limit is negative infinity. The limit does not exist because it reaches infinity as x approaches pi/2 and the limits are the same when the value is approached from the opposite directions.