Question

Evaluate the limit as x approaches pi/2 from the right of tan x.

I know the answer is - infinity but please explain the answer because I do not understand it.

Answer 1

@james, u wanted to talk?

Answer 2

Remember that tan x = sin x / cos x. Now as x --> pi/2+ (i.e., to pi/2 from the right) then
sin x --> 1
cos x is negative and --> 0

So for x close to pi/2 but greater than pi/2, sin x / cos x is negative and as x --> pi/2+, it becomes larger and larger negative.

Answer 3

@saifoo, to chat

Answer 4

Thank you James =)