Can someone help me prove that the cardA does not equal cardP?(adsbygoogle = window.adsbygoogle || []).push({});

where A is the set {a,b} and P is its power set{empty set,(a),(b),(a,b)}

I know that by showing A ->P is not a surjection, I will be showing that no bijection exists and thus unequal cardinalities between sets A and P. But I am unclear on how to do this. I heard it is a tough proof, and just want some insight of helpful hints.

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# Can someone help me prove that the cardA does not equal cardP?

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