যদি \( A \) এবং \( B \) ধনাত্মক সূক্ষ্মকোণ হয়, এবং \( \tan A = \frac{1}{2} \) ও \( \tan B = \frac{1}{3} \) হয়, তাহলে \( A + B = ? \) (If \( A \) and \( B \) are positive acute angle, and \( \tan A = \frac{1}{2} \) and \( \tan B = \frac{1}{3} \), then \( A + B = ? \))
