saurster wrote:

I think the correct answer is A

My reasoning,

X^4 + y^4 = 100, so the greatest value of X would be when Y is minimized, so assume Y = 0;

So X^4 = 100

=> X^2 = 10

=> X = Sqrt(10)

=> so x > 3 and X <4

now, looking at the answer choices, if we assume Y has some value, we can safely assume that X is between 0 and 3

What is OA; i am torn between A or B, but if I had to guess, I would choose A

I did so, ( under time pressure of course! ) and it turned out to be wrong!