



 
Hi Jerry. The two parts of the question seem the same to me. Here's how I would solve it. Let c = a^{6}. Then 1/c = 1/a^{6} = b^{6}. Then we are to show that: c + 4/c > 4 for all positive real values of c. Since c is positive, we can multiply both sides by c, then see a quadratic: c^{2} + 4 > 4c which is a perfect square: (c  2)^{2} > 0 So the value of c = 2 is the only problem here. Can you complete the question now?  


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