# ISI2015-MMA-31

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Consider the sets defined by the real solutions of the inequalities

$$A = \{(x,y):x^2+y^4 \leq 1 \} \:\:\:\:\:\:\:\: B = \{ (x,y):x^4+y^6 \leq 1\}$$

Then

1. $B \subseteq A$
2. $A \subseteq B$
3. Each of the sets $A – B, \: B – A$ and $A \cap B$ is non-empty
4. none of the above

edited

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