Correct answer: 8
As x approaches π/4, cot³(x) approaches 1 and tan(x) also approaches 1, making the numerator approach 0. The denominator, cos(x + π/4), approaches 0 as well, leading to an indeterminate form. Applying L'Hôpital's Rule, we differentiate the numerator and denominator, ultimately simplifying to find that the limit evaluates to 8.