Exams › JEE Main › Maths › Basic Mathematics / Inequalities
1 questions with worked solutions.
Q1. For a, b belonging to the positive reals, find the minimum possible value of (a + b)*(1/a + 1/b).
Answer: 4
Expanding gives 2 + a/b + b/a. By AM-GM, a/b + b/a >= 2, so the whole expression is at least 4, achieved at a = b.