Well, this is the same thing as the limit as x approaches pi. Tangent of x is sine of x over cosine of x. And so both of these are defined for pi. And so we could just substitute pi in. And we just want to ensure that we don't get a zero in the denominator, because that would make it undefined. So we get sine of pi over cosine of pi, which is equal to zero over negative one, which is completely fine. If it was negative one over zero, we'd be in trouble.